Author: "Charlotte Vastel" / Topic: 010303 astronomy & astrophysics - Searchworks@Jio Institute Digital Library Search Results

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1. FAUST II. Discovery of a Secondary Outflow in IRAS 15398-3359: Variability in Outflow Direction during the Earliest Stage of Star Formation?

Author: Cécile Favre, Serena Viti, Luke T. Maud, Davide Fedele, S. Mercimek, Anna Miotello, Naoki Watanabe, Spandan Choudhury, Siyi Feng, Charlotte Vastel, Ross O'Donoghue, Brian Svoboda, Ci Xue, Claudine Kahane, Yuki Okoda, Doug Johnstone, Yoshimasa Watanabe, Andrea Isella, C. Codella, Yoko Oya, Linda Podio, Nami Sakai, J. Ospina-Zamudio, G. A. Moellenbrock, Aurora Durán, Yancy L. Shirley, Jaime E. Pineda, Paola Caselli, Yasuhiro Oba, François Dulieu, Laurent Loinard, Leonardo Testi, Muneaki Imai, Takeshi Sakai, Arezu Witzel, María José Maureira, Tomoyuki Hanawa, Francesco Fontani, Izaskun Jiménez-Serra, Lucy Evans, Marta De Simone, Felipe O. Alves, Logan Francis, Vianney Taquet, Dominique Segura-Cox, Emmanuel Caux, Mathilde Bouvier, Riouhei Nakatani, Bertrand Lefloch, Yichen Zhang, Nadia Balucani, Cecilia Ceccarelli, Tetsuya Hama, Satoshi Yamamoto, H. Nomura, Claire J. Chandler, Albert Rimola, Bo Zhao, Shoji Mori, Shu-ichiro Inutsuka, Tomoya Hirota, Satoshi Ohashi, Nadia M. Murillo, Eric Herbst, Steven B. Charnley, E. Bianchi, Ana López-Sepulcre, Yuri Aikawa, Francois Menard, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA (UMR_8112)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY), Okoda, Y. [0000-0003-3655-5270], Oya, Y. [0000-0002-0197-8751], Francis, L. [0000-0001-8822-6327], Johnstone, D. [0000-0002-6773-459X], Inutsuka, S. I. [0000-0003-4366-6518], Ceccarelli, C. [0000-0001-9664-6292], Codella, C. [0000-0003-1514-3074], Chandler, C. [0000-0002-7570-5596], Sakai, N. [0000-0002-3297-4497], Aikawa, Y. [0000-0003-3283-6884], Alves, F. [0000-0002-7945-064X], Balucani, N. [0000-0001-5121-5683], Bianchi, E. [0000-0001-9249-7082], Bouvier, M. [0000-0003-0167-0746], Caselli, P. [0000-0003-1481-7911], De Simone, M. [0000-0001-5659-0140], Feng, S. [0000-0002-4707-8409], Fontani, F. [0000-0003-0348-3418], Hama, T. [0000-0002-4991-4044], Hanawa, T. [0000-0002-7538-581X], Herbst, E. [0000-0002-4649-2536], Hirota, T. [0000-0003-1659-095X], Imai, M. [0000-0002-5342-6262], Isella, A. [0000-0001-8061-2207], Jiménez Serra, I. [0000-0003-4493-8714], Kahane, C. [0000-0003-1691-4686], Loinard, L. [0000-0002-5635-3345], López Sepulcre, A. [0000-0002-6729-3640], Maud, L. T. [0000-0002-7675-3565], Maureira, M. J. [0000-0002-7026-8163], Menard, F. [0000-0002-1637-7393], Miotello, A. [0000-0002-7997-2528], Moellenbrock, G. [0000-0002-3296-8134], Oba, Y. [0000-0002-6852-3604], Ohashi, S. [0000-0002-9661-7958], Pineda, J. E. [0000-0002-3972-1978], Rimola, A. [0000-0002-9637-4554], Sakai, T. [0000-0003-4521-7492], Segura Cox, D. [0000-0003-3172-6763], Svoboda, B. [0000-0002-8502-6431], Taquet, V. [0000-0003-0407-7489], European Research Council (ERC), Agencia Estatal de Investigación (AEI), and Japan Society for the Promotion of Science (JSPS)
Subjects: Astrochemistry, FOS: Physical sciences, Astrophysics, 01 natural sciences, 7. Clean energy, Submillimeter Array, Stellar jets, Interstellar medium, 0103 physical sciences, Protostar, 010303 astronomy & astrophysics, Shocks, Solar and Stellar Astrophysics (astro-ph.SR), Line (formation), Astrochimica, Physics, [PHYS]Physics [physics], Accretion (meteorology), 010308 nuclear & particles physics, Star formation, Astronomy and Astrophysics, Interstellar molecules, Astrophysics - Astrophysics of Galaxies, Young stellar objects, Protostars, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Outflow, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: We have observed the very low-mass Class 0 protostar IRAS 15398−3359 at scales ranging from 50 to 1800 au, as part of the Atacama Large Millimeter/Submillimeter Array Large Program FAUST. We uncover a linear feature, visible in H2CO, SO, and C18O line emission, which extends from the source in a direction almost perpendicular to the known active outflow. Molecular line emission from H2CO, SO, SiO, and CH3OH further reveals an arc-like structure connected to the outer end of the linear feature and separated from the protostar, IRAS 15398−3359, by 1200 au. The arc-like structure is blueshifted with respect to the systemic velocity. A velocity gradient of 1.2 km s−1 over 1200 au along the linear feature seen in the H2CO emission connects the protostar and the arc-like structure kinematically. SO, SiO, and CH3OH are known to trace shocks, and we interpret the arc-like structure as a relic shock region produced by an outflow previously launched by IRAS 15398−3359. The velocity gradient along the linear structure can be explained as relic outflow motion. The origins of the newly observed arc-like structure and extended linear feature are discussed in relation to turbulent motions within the protostellar core and episodic accretion events during the earliest stage of protostellar evolution. The authors thank the anonymous reviewer for invaluable comments. They are also grateful to Hauyu Baobab Liu for useful discussions. This paper makes use of the following ALMA data set: ADS/JAO.ALMA#2018.1.01205.L (PI: Satoshi Yamamoto). ALMA is a partnership of the ESO (representing its member states), the NSF (USA) and NINS (Japan), together with the NRC (Canada) and the NSC and ASIAA (Taiwan), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by the ESO, the AUI/NRAO, and the NAOJ. The authors thank to the ALMA staff for their excellent support. This work is supported by the projects PRIN-INAF-MAIN-STREAM 2017 Protoplanetary disks seen through the eyes of new-generation instruments, ARIEL and the astrochemical link between circumstellar disks and planets, and the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programmes: The Dawn of Organic Chemistry (DOC), grant agreement No. 741002, and Astro-Chemistry Origins (ACO), grant No. 811312. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. I.J.-S. has received partial support from the Spanish FEDER (project number ESP2017-86582-C4-1-R) and the State Research Agency (AEI; project number PID2019-105552RB-C41). D.J. is supported by NRC Canada and by an NSERC Discovery Grant. This project is also supported by a Grant-in-Aid from Japan Society for the Promotion of Science (KAKENHI: Nos. 18H05222, 19H05069, 19K14753). Yuki Okoda thanks the Advanced Leading Graduate Course for Photon Science (ALPS) and Japan Society for the Promotion of Science (JSPS) for financial support. Peerreview
Published: 2021
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2. HCN/HNC chemistry in shocks

Author: E. Mendoza, Serena Viti, Linda Podio, Rafael Bachiller, P. R. Rivera-Ortiz, Bertrand Lefloch, Charlotte Vastel, M. Benedettini, Gemma Busquet, Jacques Raymond Daniel Lépine, C. Codella, A Schutzer, Agence Nationale de la Recherche (France), European Commission, European Research Council, Fundações de Amparo à Pesquisa (Brasil), Ministerio de Ciencia, Innovación y Universidades (España), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), University College of London [London] (UCL), Centro de Investigaciones Energéticas Medioambientales y Tecnológicas [Madrid] (CIEMAT), Istituto di Astrofisica e Planetologia Spaziali - INAF (IAPS), Istituto Nazionale di Astrofisica (INAF), and INAF - Osservatorio Astrofisico di Arcetri (OAA)
Subjects: FOS: Physical sciences, Astrophysics, 01 natural sciences, ISM: abundances, jets and outflow -ISM, Jets and Outflows, Methods: observational, Abundance (ecology), 0103 physical sciences, astrochemistry -methods, Radiative transfer, Methods, Protostar, Molecule, Isotopologue, observational [Methods], Abundances, 010306 general physics, 010303 astronomy & astrophysics, Observational, molecules [ISM], ISM, Astrochemistry, abundances [ISM], Molecular line, Chemistry, jets and outflows [ISM], Molecular cloud, molecules -ISM, Astronomy and Astrophysics, observational -ISM, Molecules, Astrophysics - Astrophysics of Galaxies, ISM: molecules, ISM: jets and outflows, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], Excitation
Abstract: HCN and its isomer HNC play an important role in molecular cloud chemistry and the formation of more complex molecules. We investigate here the impact of protostellar shocks on the HCN and HNC abundances from high-sensitivity IRAM 30m observations of the prototypical shock region L1157-B1 and the envelope of the associated Class 0 protostar, as a proxy for the pre-shock gas. The isotopologues H$^{12}$CN, HN$^{12}$C, H$^{13}$CN, HN$^{13}$C, HC$^{15}$N, H$^{15}$NC, DCN and DNC were all detected towards both regions. Abundances and excitation conditions were obtained from radiative transfer analysis of molecular line emission under the assumption of Local Thermodynamical Equilibrium. In the pre-shock gas, the abundances of the HCN and HNC isotopologues are similar to those encountered in dark clouds, with a HCN/HNC abundance ratio $\approx 1$ for all isotopologues. A strong D-enrichment (D/H$\approx 0.06$) is measured in the pre-shock gas. There is no evidence of $^{15}$N fractionation neither in the quiescent nor in the shocked gas. At the passage of the shock, the HCN and HNC abundances increase in the gas phase in different manners so that the HCN/HNC relative abundance ratio increases by a factor 20. The gas-grain chemical and shock model UCLCHEM allows us to reproduce the observed trends for a C-type shock with pre-shock density $n$(H)= $10^5$cm$^{-3}$ and shock velocity $V_s= 40$km/s. We conclude that the HCN/HNC variations across the shock are mainly caused by the sputtering of the grain mantle material in relation with the history of the grain ices., Comment: 14 pages, 7 figures. Accepted for publication in MNRAS
Published: 2021

3. Seeds of Life in Space (SOLIS)

Author: R. Neri, C. Codella, M. Benedettini, Cecilia Ceccarelli, Linda Podio, Bertrand Lefloch, Gemma Busquet, Francesco Fontani, S. Viti, Charlotte Vastel, Ana López-Sepulcre, E. Bianchi, S. Spezzano, and Paola Caselli
Subjects: Shock wave, Physics, Solar System, 010504 meteorology & atmospheric sciences, Period (periodic table), Star (game theory), Astrophysics - astrophysics of galaxies, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Space (mathematics), 01 natural sciences, Isotopes of nitrogen, ISM: molecules, Interstellar medium, ISM: jets and outflows, ISM: individual objects: L1157, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Protostar, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences
Abstract: The isotopic ratio of nitrogen presents a wide range of values in the Solar System and in star forming system whose origin is still unclear. Chemical reactions in the gas phase are one of the possible processes that could modify the $^{14}$N/$^{15}$N ratio. We aim at investigating if and how the passage of a shock wave in the interstellar medium, can affect the relative fraction of nitrogen isotopes. The ideal place for such a study is the L1157 outflow, where several shocked clumps are present. We present the first measurement of the $^{14}$N/$^{15}$N ratio in the two shocked clumps, B1 and B0, of the protostellar outflow L1157, derived from the interferomteric maps of the H$^{13}$CN(1-0) and the HC$^{15}$N(1-0) lines. In B1, we find that the H$^{13}$CN(1-0) and HC$^{15}$N(1-0) emission traces the front of the clump, with averaged column density of $N$(H$^{13}$CN) $\sim$ 7$\times$10$^{12}$ cm$^{-2}$ and $N$(HC$^{15}$N) $\sim$ 2$\times$10$^{12}$ cm$^{-2}$. In this region the ratio H$^{13}$CN(1-0)/HC$^{15}$N(1-0) is quite uniform with an average value of $\sim$ 5$\pm$1. The same average value is also measured in the smaller clump B0e. Assuming the standard $^{12}$C/$^{13}$C = 68, we obtain $^{14}$N/$^{15}$N = 340$\pm$70, similar to those usually found in prestellar cores and protostars. We analysed the prediction of a chemical shock model for several shock conditions and we found that the nitrogen and carbon fractionations do not vary much for the first period after the shock. The observed H$^{13}$CN/HC$^{15}$N can be reproduced by a non-dissociative, C-type shock with parameters in agreement with previous modelling of L1157-B1. Both observations and chemical models indicate that the shock propagation does not affect the nitrogen isotopic ratio that remains similar to that measured in lower temperature gas in prestellar cores and in protostellar envelopes., 7 pages, 6 figures
Published: 2021

4. A Decade with VAMDC: Results and Ambitions

Author: Carlo Maria Zwölf, A. J. Markwick, Anastasiya A. Lukashevskaya, Tom J. Millar, Patrick Palmeri, M. Emoto, Yuri Ralchenko, Thomas Marquart, Felix Duensing, Evelyne Roueff, Duck-Hee Kwon, Pascal Quinet, Johannes Postler, Julien Penguen, Izumi Murakami, Vincent Boudon, Bobby Antony, Paul Scheier, Milan S. Dimitrijević, Christine Joblin, Valery I. Perevalov, Vladimir G. Tyuterev, Jean-Michel Glorian, Tatiana Ryabchikova, Valentine Wakelam, E. Krishnakumar, Igor Y.-U. Skobelev, Philippe Bollard, Guy Rixon, Laurence S. Rothman, Sylvie Sahal-Bréchot, Giacomo Mulas, Damien Albert, Nicolas Moreau, Bernard Schmitt, Alexandr Z. Fazliev, Peter Schilke, Giulio Del Zanna, Stephan Schlemmer, Eric Stempels, Nicholas A. Walton, Bratislav P. Marinković, Serguey A. Tashkun, Charlotte Vastel, Yury Pakhomov, Claudio Mendoza, K. W. Smith, Thomas Möller, Oleg M. Lyulin, Brian J. Drouin, Roman V. Kochanov, Alexei I. Privezentsev, Vladimir A. Srećković, Darko Jevremović, Giuseppe Leto, Iouli E. Gordon, Serguei V. Morozov, Nigel J. Mason, C. J. Zeippen, Yong-Joo Rhee, Petr A. Loboda, Veljko Vujčić, Pierre Gratier, Jonathan Tennyson, Marie-Lise Dubernet, Cyril Richard, Franck Delahaye, Christian Hill, Yuri L. Babikov, Christian P. Endres, Holger S. P. Müller, Nikolai Piskunov, Yaye Awa Ba, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), Department of Environmental, Earth, and Atmospheric Sciences [Lowell], University of Massachusetts [Lowell] (UMass Lowell), University of Massachusetts System (UMASS)-University of Massachusetts System (UMASS), Groupe de spectrométrie moléculaire et atmosphérique (GSMA), Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA (UMR_8112)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY), Laboratoire Interdisciplinaire Carnot de Bourgogne [Dijon] (LICB), Université de Bourgogne (UB)-Université de Technologie de Belfort-Montbeliard (UTBM)-Centre National de la Recherche Scientifique (CNRS), FORMATION STELLAIRE 2020, Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), LERMA Cergy (LERMA), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, INAF - Osservatorio Astronomico di Cagliari (OAC), Istituto Nazionale di Astrofisica (INAF), Del Zanna, Giulio [0000-0002-4125-0204], Walton, Nicholas [0000-0003-3983-8778], Apollo - University of Cambridge Repository, Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique et Atmosphères = Laboratory for Studies of Radiation and Matter in Astrophysics and Atmospheres (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY), Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), Université de Technologie de Belfort-Montbeliard (UTBM)-Université de Bourgogne (UB)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), and Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY)-École normale supérieure - Paris (ENS-PSL)
Subjects: Nuclear and High Energy Physics, 010504 meteorology & atmospheric sciences, Data management, Atom and Molecular Physics and Optics, Interoperability, interoperability, 01 natural sciences, Field (computer science), Resource (project management), 0103 physical sciences, lcsh:Nuclear and particle physics. Atomic energy. Radioactivity, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, open access, [PHYS]Physics [physics], atomic and molecular data, scientific databases, FAIR principles, business.industry, Condensed Matter Physics, Data science, Atomic and Molecular Physics, and Optics, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, lcsh:QC770-798, Data center, Atom- och molekylfysik och optik, business, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: This paper presents an overview of the current status of the Virtual Atomic and Molecular Data Centre (VAMDC) e-infrastructure, including the current status of the VAMDC-connected (or to be connected) databases, updates on the latest technological development within the infrastructure and a presentation of some application tools that make use of the VAMDC e-infrastructure. We analyse the past 10 years of VAMDC development and operation, and assess their impact both on the field of atomic and molecular (A&amp, M) physics itself and on heterogeneous data management in international cooperation. The highly sophisticated VAMDC infrastructure and the related databases developed over this long term make them a perfect resource of sustainable data for future applications in many fields of research. However, we also discuss the current limitations that prevent VAMDC from becoming the main publishing platform and the main source of A&amp, M data for user communities, and present possible solutions under investigation by the consortium. Several user application examples are presented, illustrating the benefits of VAMDC in current research applications, which often need the A&amp, M data from more than one database. Finally, we present our vision for the future of VAMDC.
Published: 2020
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5. ALMA Survey of Orion Planck Galactic Cold Clumps (ALMASOP). II. Survey Overview : A First Look at 1.3 mm Continuum Maps and Molecular Outflows

Author: Leonardo Bronfman, Somnath Dutta, Yi-Jehng Kuan, Anthony Moraghan, Shanghuo Li, Patricio Sanhueza, Charlotte Vastel, Archana Soam, Gwanjeong Kim, Dipen Sahu, David Eden, Sheng-Yuan Liu, Naomi Hirano, Woojin Kwon, Jinhua He, Kee-Tae Kim, Neal J. Evans, Shih-Ying Hsu, Chang Won Lee, Jeong-Eun Lee, Hsien Shang, Qizhou Zhang, Sheng-Li Qin, V. M. Pelkonen, Paul F. Goldsmith, Chin-Fei Lee, Alessio Traficante, Mika Juvela, Di Li, Ken'ichi Tatematsu, Yuefang Wu, Kai Syun Jhan, Derek Ward-Thompson, Doug Johnstone, Tie Liu, and Department of Physics
Subjects: Research program, 010504 meteorology & atmospheric sciences, Library science, FOS: Physical sciences, 01 natural sciences, Dense interstellar clouds, DENSE CORES, Star forming regions, Stellar jets, Interstellar medium, 0103 physical sciences, Natural science, China, CHEMICAL DIFFERENTIATION, COLLAPSE, 010303 astronomy & astrophysics, TEMPERATURE, Solar and Stellar Astrophysics (astro-ph.SR), 0105 earth and related environmental sciences, Astrochemistry, Physics, SPECTROSCOPY, Star formation, Early stellar evolution, Stellar winds, Astronomy and Astrophysics, 115 Astronomy, Space science, Chinese academy of sciences, Astrophysics - Astrophysics of Galaxies, BIPOLAR OUTFLOWS, EVOLUTION, Stellar wind, Protostars, DARK CLOUDS, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, Research council, Astrophysics of Galaxies (astro-ph.GA), ROTATION, CLOUD CORES, Christian ministry, Low mass stars, Engineering research, Stellar abundances, Spectral energy distribution
Abstract: Planck Galactic Cold Clumps (PGCCs) are contemplated to be the ideal targets to probe the early phases of star formation. We have conducted a survey of 72 young dense cores inside PGCCs in the Orion complex with the Atacama Large Millimeter/submillimeter Array (ALMA) at 1.3\,mm (band 6) using three different configurations (resolutions $\sim$ 0$\farcs$35, 1$\farcs$0, and 7$\farcs$0) to statistically investigate their evolutionary stages and sub-structures. We have obtained images of the 1.3\,mm continuum and molecular line emission ($^{12}$CO, and SiO) at an angular resolution of $\sim$ 0$\farcs$35 ($\sim$ 140\,au) with the combined arrays. We find 70 substructures within 48 detected dense cores with median dust-mass $\sim$ 0.093\,M$_{\sun}$ and deconvolved size $\sim$ 0$\farcs$27. Dense substructures are clearly detected within the central 1000\,au of four candidate prestellar cores. The sizes and masses of the substructures in continuum emission are found to be significantly reduced with protostellar evolution from Class\,0 to Class\,I. We also study the evolutionary change in the outflow characteristics through the course of protostellar mass accretion. A total of 37 sources exhibit CO outflows, and 20 ($>$50\%) show high-velocity jets in SiO. The CO velocity-extents ($\Delta$Vs) span from 4 to 110 km/s with outflow cavity opening angle width at 400\,au ranging from $[\Theta_{obs}]_{400}$ $\sim$ 0$\farcs$6 to 3$\farcs$9, which corresponds to 33$\fdg$4$-$125$\fdg$7. For the majority of the outflow sources, the $\Delta$Vs show a positive correlation with $[\Theta_{obs}]_{400}$, suggesting that as protostars undergo gravitational collapse, the cavity opening of a protostellar outflow widens and the protostars possibly generate more energetic outflows., Comment: 43 pages, 25 figures (14 in the main text, 9 in the appendix), accepted for publication in the Astrophysical Journal Supplement Series (ApJS)
Published: 2020

6. FAUST I. The hot corino at the heart of the prototypical Class I protostar L1551 IRS5

Author: Nadia Balucani, Tetsuya Hama, Bo Zhao, C. Favre, Yancy L. Shirley, Brian Svoboda, H. Nomura, Francois Menard, Yasuhiro Oba, G. Moellenbrock, Laurent Loinard, Charlotte Vastel, M. Bouvier, Shoji Mori, Andrea Isella, François Dulieu, Leonardo Testi, S. Yamamoto, E. Bianchi, Spandan Choudhury, Nami Sakai, M. De Simone, Aurora Durán, Linda Podio, Luke T. Maud, S. Mercimek, Jaime E. Pineda, D. Johnstone, Y. Oya, D. Segura Cox, P. Caselli, Ana López-Sepulcre, Claudine Kahane, Y. Aikawa, Bertrand Lefloch, M. J. Maureira, L. Evans, C. Codella, I. Jimenez-Serra, M. Imai, Naoki Watanabe, Francesco Fontani, S. Ohashi, Siyi Feng, Felipe O. Alves, Anna Miotello, Claire J. Chandler, Logan Francis, Ci Xue, Emmanuel Caux, Andrea Lusvarghi Witzel, Eric Herbst, Albert Rimola, Vianney Taquet, Steven B. Charnley, Cecilia Ceccarelli, Yoshimasa Watanabe, Y. Zhang, Davide Fedele, R. Nakatani, J. Ospina-Zamudio, Y. Okoda, Tomoya Hirota, Takeshi Sakai, S. Viti, Tomoyuki Hanawa, Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737, Balucani, N. [0000-0001-5121-5683], De Oliveira Alves, F. [0000-0002-7945-064X], Hama, T. [0000-0002-4991-4044], Ohashi, S. [0000-0002-9661-7958], Johnstone, D. [0000-0002-6773-459X], Watanabe, Y. [0000-0002-9668-3592], Ceccarelli, C. [0000-0001-9664-6292], Pineda, J. [0000-0002-3972-1978], Fedele, D. [0000-0001-6156-0034], Mercimek, S. [0000-0002-0742-7934], Xue, C. [0000-0003-2760-2119], Sakai, N. [0000-0002-3297-4497], European Research Council (ERC), Japan Society for the Promotion of Science (KAKENHI), Agencia Estatal de Investigación (AEI), Universidad Nacional Autónoma de México (UNAM), Agence Nationale de la Recherche (ANR), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), Department of Materials Science and Engineering, Shibaura Institute of Technology, Japan Society for the Promotion of Science (KAKENHI), 18H05222 19H05069 19K14753, Ministerio de Economía y Competitividad (MINECO), Universidad Nacional Autónoma de México (UNAM) IN112417 IN112820, and French National Research Agency (ANR), ANR-16-CE31-0013 ANR-15-IDEX-02
Subjects: Astrochemistry, 010504 meteorology & atmospheric sciences, Methyl formate, FOS: Physical sciences, Astrophysics, 01 natural sciences, chemistry.chemical_compound, Planet, Phase (matter), 0103 physical sciences, Protostar, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), formation [Stars], molecules [ISM], 0105 earth and related environmental sciences, Physics, Astrochimica, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astronomy and Astrophysics, Radius, Planetary system, Astrophysics - Astrophysics of Galaxies, chemistry, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics of Galaxies (astro-ph.GA), Methanol, [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA]
Abstract: Bianchi, E. et al., The study of hot corinos in solar-like protostars has been so far mostly limited to the Class 0 phase, hampering our understanding of their origin and evolution. In addition, recent evidence suggests that planet formation starts already during Class I phase, which therefore represents a crucial step in the future planetary system chemical composition. Hence, the study of hot corinos in Class I protostars has become of paramount importance. Here, we report the discovery of a hot corino towards the prototypical Class I protostar L1551 IRS5, obtained within the ALMA (Atacama Large Millimeter/submillimeter Array) Large Program FAUST (Fifty AU STudy of the chemistry in the disc/envelope system of solar-like protostars).We detected several lines from methanol and its isotopologues (13CH3OH and CH2DOH), methyl formate, and ethanol. Lines are bright towards the north component of the IRS5 binary system, and a possible second hot corino may be associated with the south component. The methanol lines' non-LTE analysis constrains the gas temperature (100 K), density (1.5 × 108 cm3), and emitting size (10 au in radius). All CH3OH and 13CH3OH lines are optically thick, preventing a reliable measure of the deuteration. The methyl formate and ethanol relative abundances are compatible with those measured in Class 0 hot corinos. Thus, based on this work, little chemical evolution from Class 0 to I hot corinos occurs., With funding from the Spanish government through the "María de Maeztu Unit of Excellence" accreditation (MDM-2017-0737)
Published: 2020
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7. A 3mm chemical exploration of small organics in Class I YSOs

Author: Jane Huang, Bertrand Lefloch, Ana López-Sepulcre, E. Bianchi, Francois Menard, Charlotte Vastel, Charles J. Law, Cecilia Ceccarelli, Karin I. Öberg, Romane Le Gal, Cécile Favre, Umeå University, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), and Centre National d'Études Spatiales [Toulouse] (CNES)
Subjects: Class (set theory), Astrochemistry, 010504 meteorology & atmospheric sciences, FOS: Physical sciences, IRAS 04016+2610, Astrophysics, 01 natural sciences, IRAS 04166+2706, 0103 physical sciences, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), 0105 earth and related environmental sciences, Physics, IRAS 04365+2535, Earth and Planetary Astrophysics (astro-ph.EP), YSOs: individual (IRAS 04181+2654A, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, IRAS 04169+2702, IRAS 04302+2247), Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), IRAS 04295+2251, [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], Astrophysics - Earth and Planetary Astrophysics
Abstract: There is mounting evidence that the composition and structure of planetary systems are intimately linked to their birth environments. During the past decade, several spectral surveys probed the chemistry of the earliest stages of star formation and of late planet-forming disks. However, very little is known about the chemistry of intermediate protostellar stages, i.e. Class I Young Stellar Objects (YSOs), where planet formation may have already begun. We present here the first results of a 3mm spectral survey performed with the IRAM-30m telescope to investigate the chemistry of a sample of seven Class I YSOs located in the Taurus star-forming region. These sources were selected to embrace the wide diversity identified for low-mass protostellar envelope and disk systems. We present detections and upper limits of thirteen small ($N_{\rm atoms}\leq3$) C, N, O, and S carriers - namely CO, HCO$^+$, HCN, HNC, CN, N$_2$H$^+$, C$_2$H, CS, SO, HCS$^+$, C$_2$S, SO$_2$, OCS - and some of their D, $^{13}$C, $^{15}$N, $^{18}$O, $^{17}$O, and $^{34}$S isotopologues. Together, these species provide constraints on gas-phase C/N/O ratios, D- and $^{15}$N-fractionation, source temperature and UV exposure, as well as the overall S-chemistry. We find substantial evidence of chemical differentiation among our source sample, some of which can be traced back to Class I physical parameters, such as the disk-to-envelope mass ratio (proxy for Class I evolutionary stage), the source luminosity, and the UV-field strength. Overall, these first results allow us to start investigating the astrochemistry of Class I objects, however, interferometric observations are needed to differentiate envelope versus disk chemistry., 27 pages, 17 figures, 4 tables, accepted for publication in ApJ
Published: 2020
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8. Efficient Methanol Production on the Dark Side of a Prestellar Core

Author: Hope Chen, Philip C. Myers, Silvia Spezzano, Alyssa A. Goodman, Romane Le Gal, Claire Rist, Yancy L. Shirley, Paola Caselli, Jaime E. Pineda, Olli Sipilae, Rolf Guesten, Rachel Friesen, Stella S. R. Offner, Andreas Burkert, Charlotte Vastel, Mika Juvela, Pierre Hily-Blant, A. Vasyunin, Alexandre Faure, Luca Bizzocchi, Laurent Wiesenfield, Anna Punanova, Jorma Harju, Erik Rosolowsky, João Alves, Stephan Schlemmer, Harju J., Pineda J.E., Vasyunin A.I., Caselli P., Offner S.S.R., Goodman A.A., Juvela M., Sipila O., Faure A., Le Gal R., Hily-Blant P., Alves J., Bizzocchi L., Burkert A., Chen H., Friesen R.K., Gusten R., Myers P.C., Punanova A., Rist C., Rosolowsky E., Schlemmer S., Shirley Y., Spezzano S., Vastel C., Wiesenfeld L., Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Aimé Cotton (LAC), Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Department of Physics, CNRS-Université de Paris-Sud, Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), and University of Helsinki, Department of Physics
Subjects: DESORPTION, Interstellar dust processe, MOLECULAR COMPOSITION, FOS: Physical sciences, DUST, Astrophysics, Interstellar molecule, 01 natural sciences, Molecular physics, Instability, Dense interstellar clouds, 010305 fluids & plasmas, chemistry.chemical_compound, CHEMISTRY, Desorption, 0103 physical sciences, WATER, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, ABSORPTION CROSS-SECTIONS, Astrochemistry, Physics, Molecular cloud, Photodissociation, Astronomy and Astrophysics, Monoxide, 115 Astronomy, Space science, Astrophysics - Astrophysics of Galaxies, CLOUD, Core (optical fiber), [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, [PHYS.ASTR.GA]Physics [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], chemistry, 13. Climate action, Space and Planetary Science, GAS, [SDU]Sciences of the Universe [physics], Astrophysics of Galaxies (astro-ph.GA), Ophiuchus, RADIATION, Methanol, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], INTERSTELLAR MATTER
Abstract: We present ALMA maps of the starless molecular cloud core Ophiuchus/H-MM1 in the lines of deuterated ammonia (ortho-NH2D), methanol (CH3OH), and sulphur monoxide (SO). The dense core is seen in NH2D emission, whereas the CH3OH and SO distributions form a halo surrounding the core. Because methanol is formed on grain surfaces, its emission highlights regions where desorption from grains is particularly efficient. Methanol and sulphur monoxide are most abundant in a narrow zone that follows the eastern side of the core. This side is sheltered from the stronger external radiation field coming from the west. We show that photodissociation on the illuminated side can give rise to an asymmetric methanol distribution, but that the stark contrast observed in H-MM1 is hard to explain without assuming enhanced desorption on the shaded side. The region of the brightest emission has a wavy structure that rolls up at one end. This is the signature of Kelvin-Helmholtz instability occurring in sheared flows. We suggest that in this zone, methanol and sulphur are released as a result of grain-grain collisions induced by shear vorticity., Accepted for publication in the Astrophysical Journal
Published: 2020
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9. Molecular Cloud Cores with High Deuterium Fraction: Nobeyama Single-Pointing Survey

Author: Minho Choi, Mika Juvela, Mark Thompson, Quang Nguyễn Lu'o'ng, Jinhua He, Satoshi Ohashi, Xing Lu, Neal J. Evans, Jungha Kim, Ryo Kandori, Isabelle Ristorcelli, O. Fehér, Hiroko Shinnaga, Gary A. Fuller, Takeshi Sakai, L. Viktor Tóth, Tie Liu, Di Li, Tomoya Hirota, Miju Kang, Yuefang Wu, Charlotte Vastel, P. Sanhueza, Sheng-Yuan Liu, Jeong-Eun Lee, Kee-Tae Kim, Gwanjeong Kim, Naomi Hirano, Hee-Weon Yi, Ke Wang, Siyi Feng, Ken'ichi Tatematsu, and Department of Physics
Subjects: Library science, FOS: Physical sciences, INITIAL CONDITIONS, 01 natural sciences, GAS TEMPERATURE, STAR-FORMATION, DENSE CORES, Clouds, 0103 physical sciences, Natural science, China, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrochemistry, Z-MACHINE, Physics, 010308 nuclear & particles physics, Star formation, Astronomy and Astrophysics, Interstellar molecules, COLLAPSING PRESTELLAR CORES, 115 Astronomy, Space science, Astrophysics - Astrophysics of Galaxies, Chinese academy of sciences, EVOLUTION, DARK CLOUDS, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), HYPERFINE-STRUCTURE, PRE-STELLAR CORES, Christian ministry
Abstract: We present the results of a single-pointing survey of 207 dense cores embedded in Planck Galactic Cold Clumps distributed in five different environments ($\lambda$ Orionis, Orion A, B, Galactic plane, and high latitudes) to identify dense cores on the verge of star formation for the study of the initial conditions of star formation. We observed these cores in eight molecular lines at 76-94 GHz using the Nobeyama 45-m telescope. We find that early-type molecules (e.g., CCS) have low detection rates and that late-type molecules (e.g., N$_2$H$^+$, c-C$_3$H$_2$) and deuterated molecules (e.g., N$_2$D$^+$, DNC) have high detection rates, suggesting that most of the cores are chemically evolved. The deuterium fraction (D/H) is found to decrease with increasing distance, indicating that it suffers from differential beam dilution between the D/H pair of lines for distant cores ($>$1 kpc). For $\lambda$ Orionis, Orion A, and B located at similar distances, D/H is not significantly different, suggesting that there is no systematic difference in the observed chemical properties among these three regions. We identify at least eight high D/H cores in the Orion region and two at high latitudes, which are most likely to be close to the onset of star formation. There is no clear evidence of the evolutionary change in turbulence during the starless phase, suggesting that the dissipation of turbulence is not a major mechanism for the beginning of star formation as judged from observations with a beam size of 0.04 pc., Comment: 55 pages, 12 Figures, 8 Tables, accepted for publication in ApJS
Published: 2020
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10. Multi-scale analysis of the Monoceros OB 1 star-forming region

Author: Douglas J. Marshall, Mika Juvela, Sung-ju Kang, David Cornu, D. Alina, Alessio Traficante, Elisabetta R. Micelotta, Patrick M. Koch, Mark G. Rawlings, Ke Wang, Yasuo Doi, Johanna Malinen, Sarolta Zahorecz, Isabelle Ristorcelli, Jinhua He, Archana Soam, Tie Liu, Rebeka Bögner, Patricio Sanhueza, J. Montillaud, Mika Saajasto, Chang Won Lee, David Eden, L. V. Toth, V. M. Pelkonen, Charlotte Vastel, Kee-Tae Kim, Univers, Transport, Interfaces, Nanostructures, Atmosphère et environnement, Molécules (UMR 6213) (UTINAM), Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), University of Helsinki, Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Liverpool John Moores University (LJMU), Academia Sinica Institute of Astronomy and Astrophysics (ASIAA), Academia Sinica, University of Hawai'i [Hilo], Tokyo University of Science [Tokyo], University of Cologne, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Department of Physics [Helsinki], Falculty of Science [Helsinki], University of Helsinki-University of Helsinki, Eötvös Loránd University (ELTE), Kavli Institute for Astronomy and Astrophysics [Beijing] (KIAA-PKU), Peking University [Beijing], European Southern Observatory (ESO), This work was supported by the Programme National 'Physique et Chimie du Milieu Interstellaire' (PCMI) of CNRS/INSU with INC/INP co-funded by CEA and CNES., funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 730562[RadioNet], The project leading to this publication has received funding from the 'Soutien à la recherche de l’observatoire' by the OSU THETA., Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Helsingin yliopisto = Helsingfors universitet = University of Helsinki, Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Helsingin yliopisto = Helsingfors universitet = University of Helsinki-Helsingin yliopisto = Helsingfors universitet = University of Helsinki, Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Department of Physics, and Particle Physics and Astrophysics
Subjects: Infrared, Population, FOS: Physical sciences, Astrophysics, Star (graph theory), 01 natural sciences, ISM: clouds, law.invention, Telescope, law, 0103 physical sciences, Protostar, education, 010303 astronomy & astrophysics, QC, QB, Physics, education.field_of_study, stars: formation, 010308 nuclear & particles physics, Star formation, extinction, Molecular cloud, Astronomy and Astrophysics, Observable, 115 Astronomy, Space science, Astrophysics - Astrophysics of Galaxies, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), dust, extinction, dust, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: Context. Current theories and models attempt to explain star formation globally, from core scales to giant molecular cloud scales. A multi-scale observational characterisation of an entire molecular complex is necessary to constrain them. We investigate star formation in G202.3+2.5, a ̃10 × 3 pc sub-region of the Monoceros OB1 cloud with a complex morphology that harbours interconnected filamentary structures. Aims: We aim to connect the evolution of cores and filaments in G202.3+2.5 with the global evolution of the cloud and to identify the engines of the cloud dynamics. Methods: In this first paper, the star formation activity is evaluated by surveying the distributions of dense cores and protostars and their evolutionary state, as characterised using both infrared observations from the Herschel and WISE telescopes and molecular line observations with the IRAM 30 m telescope. Results: We find ongoing star formation in the whole cloud, with a local peak in star formation activity around the centre of G202.3+2.5, where a chain of massive cores (10 - 50 M☉) forms a massive ridge (≳150 M☉). All evolutionary stages from starless cores to Class II protostars are found in G202.3+2.5, including a possibly starless and massive (52 M☉) core, which presents a high column density (8 × 1022 cm-2). Conclusions: All the core-scale observables we examined point to an enhanced star formation activity that is centred on the junction between the three main branches of the ramified structure of G202.3+2.5. This suggests that the increased star formation activity results from the convergence of these branches. To further investigate the origin of this enhancement, it is now necessary to extend the analysis to larger scales in order to examine the relationship between cores, filaments, and their environment. We address these points through the analysis of the dynamics of G202.3+2.5 in a joint paper. Context. Current theories and models attempt to explain star formation globally, from core scales to giant molecular cloud scales. A multi-scale observational characterisation of an entire molecular complex is necessary to constrain them. We investigate star formation in G202.3+2.5, a similar to 10 x 3 pc sub-region of the Monoceros OB1 cloud with a complex morphology that harbours interconnected filamentary structures. Aims. We aim to connect the evolution of cores and filaments in G202.3+2.5 with the global evolution of the cloud and to identify the engines of the cloud dynamics. Methods. In this first paper, the star formation activity is evaluated by surveying the distributions of dense cores and protostars and their evolutionary state, as characterised using both infrared observations from the Herschel and WISE telescopes and molecular line observations with the IRAM 30 m telescope. Results. We find ongoing star formation in the whole cloud, with a local peak in star formation activity around the centre of G202.3+2.5, where a chain of massive cores (10 50 M-circle dot) forms a massive ridge (greater than or similar to 150 M-circle dot). All evolutionary stages from starless cores to Class II protostars are found in G202.3+2.5, including a possibly starless and massive (52 M-circle dot) core, which presents a high column density (8 x 10(22) cm(-2)). Conclusions. All the core-scale observables we examined point to an enhanced star formation activity that is centred on the junction between the three main branches of the ramified structure of G202.3+2.5. This suggests that the increased star formation activity results from the convergence of these branches. To further investigate the origin of this enhancement, it is now necessary to extend the analysis to larger scales in order to examine the relationship between cores, filaments, and their environment. We address these points through the analysis of the dynamics of G202.3+2.5 in a joint paper.
Published: 2019
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11. Sulfur-bearing Species Tracing the Disk/Envelope System in the Class I Protostellar Source Elias 29

Author: Charlotte Vastel, Bertrand Lefloch, Tomoya Hirota, Takeshi Sakai, Claudine Kahane, Nami Sakai, Cecilia Ceccarelli, Yoshimasa Watanabe, Aya E. Higuchi, Yuri Aikawa, Yoko Oya, Ana López-Sepulcre, Satoshi Yamamoto, Emmanuel Caux, University of Electro-Communications [Tokyo] (UEC), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), RIKEN - Institute of Physical and Chemical Research [Japon] (RIKEN), Graduate School of Frontier Sciences, The University of Tokyo (UTokyo), Department of Earth and Planetary Sciences [Kobe], Kobe University, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), The University of Tokyo, Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), and Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010504 meteorology & atmospheric sciences, FOS: Physical sciences, chemistry.chemical_element, Astrophysics, 01 natural sciences, 7. Clean energy, Submillimeter Array, Spectral line, Organic molecules, 0103 physical sciences, Protostar, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Envelope (waves), Line (formation), Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Sulfur, Astrophysics - Solar and Stellar Astrophysics, chemistry, 13. Climate action, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics of Galaxies (astro-ph.GA), Millimeter
Abstract: We have observed the Class I protostellar source Elias 29 with Atacama Large Millimeter/submillimeter Array (ALMA). We have detected CS, SO, $^{34}$SO, SO$_2$, and SiO line emissions in a compact component concentrated near the protostar and a ridge component separated from the protostar by 4\arcsec\ ($\sim 500$ au). The former component is found to be abundant in SO and SO$_2$ but deficient in CS. The abundance ratio SO/CS is as high as $3^{+13}_{-2} \times 10^2$ at the protostar, which is even higher than that in the outflow-shocked region of L1157 B1. However, organic molecules (HCOOCH$_3$, CH$_3$OCH$_3$, CCH, and c-C$_3$H$_2$) are deficient in Elias 29. We attribute the deficiency in organic molecules and richness in SO and SO$_2$ to the evolved nature of the source or the relatively high dust temperature (\protect\raisebox{-0.7ex}{$\:\stackrel{\textstyle >}{\sim}\:$} 20 K) in the parent cloud of Elias 29. The SO and SO$_2$ emissions trace rotation around the protostar. Assuming a highly inclined configuration ($i \geq 65$\degr; 0\degr\ for a face-on configuration) and Keplerian motion for simplicity, the protostellar mass is estimated to be (0.8 -- 1.0) \Msun. The $^{34}$SO and SO$_2$ emissions are asymmetric in their spectra; the blue-shifted components are weaker than the red-shifted ones. Although this may be attributed to the asymmetric molecular distribution, other possibilities are also discussed.
Published: 2019
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12. SCOPE: SCUBA-2 Continuum Observations of Pre-protostellar Evolution – Survey Description and Compact Source Catalogue

Author: Karine Demyk, Mark G. Rawlings, Giuseppe Cosentino, Lixia Yuan, Gwanjeong Kim, Dimitris Stamatellos, Satoshi Ohashi, Dalei Li, Yasuo Doi, L. Harvey-Smith, Archana Soam, Anthony Peter Whitworth, Mark Thompson, Izaskun Jiménez-Serra, Gary A. Fuller, Huei-Ru Chen, Tae-Geun Ji, Oscar Morata, Chakali Eswaraiah, Jinyi Yang, Takeshi Sakai, Y. L. Yuan, Hiroko Shinnaga, David Cornu, Jonathan Rawlings, Walter Kieran Gear, Shaila Akhter, Yuri Aikawa, A. Chrysostomou, Fanyi Meng, Andrew Walsh, Christine D. Wilson, P. M. McGehee, M. Chen, Tomoya Hirota, Carsten Henkel, You-Hua Chu, E. Falgarone, S. Kim, Yuxin He, Johanna Malinen, Sung-ju Kang, Chin-Fei Lee, Xuepeng Chen, Miju Kang, Annie Hughes, V.-M. Pelkonen, Graham S. Bell, Woojin Kwon, Huawei Zhang, Bon-Chul Koo, E. Jarken, Glenn J. White, J. X. Ge, Andrew Rigby, A-Ran Lyo, Wayne S. Holland, Hong-Li Liu, Geumsook Park, Mengyao Tang, Emily Drabek-Maunder, Hee-Weon Yi, M. Liu, Tie Liu, Rebeka Bögner, J.-P. Bernard, C. P. Zhang, B. S. Wang, Manash R. Samal, Harriet Parsons, Mika Juvela, Toby J. T. Moore, Lei Zhu, Ya-Wen Tang, Guobao Zhang, Leonardo Bronfman, George J. Bendo, S. Mairs, Serena Viti, H. Wang, Tetsuo Hasegawa, Yuxin Lin, Minho Choi, Zhiyuan Ren, Ke Wang, Yi-Jehng Kuan, David Eden, I. Ristorcelli, Lei Qian, X. Chen, Paul F. Goldsmith, Jinhua He, Diego Mardones, Shih-Ping Lai, Di Li, Soojong Pak, Qizhou Zhang, Ken'ichi Tatematsu, L. Montier, Yuefang Wu, C. Zhou, Guido Garay, Patricio Sanhueza, A. Rivera-Ingraham, Nicolas Peretto, Keping Qiu, Siyi Feng, Patrick M. Koch, Neal J. Evans, Jeong-Eun Lee, Andrew Blain, A. P. Marston, Hua-bai Li, M. Fich, Chao Zhang, Eun Jung Chung, G. Luo, J. Montillaud, Derek Ward-Thompson, Jianjun Zhou, Maria Cunningham, Jungha Kim, N. Lo, Roberta Paladini, J. Di Francesco, Jongsoo Kim, Ye Xu, Xing Lu, Charlotte Vastel, Chang Won Lee, Pak Shing Li, John A. P. Lopez, Per Friberg, Sheng-Li Qin, Gerald Moriarty-Schieven, D. Alina, G. Pech, Wen Ping Chen, O. Fehér, Pei Zuo, Sheng-Yuan Liu, Jinghua Yuan, Scott Chapman, Alessio Traficante, Doug Johnstone, Jane Greaves, Do-Young Byun, Naomi Hirano, Helen J. Fraser, Jiali Wang, Koji S. Kawabata, J. G. A. Wouterloot, X. Guan, Hsien Shang, Annie Zavagno, John Richer, Kee-Tae Kim, Sarolta Zahorecz, Kate Pattle, Y. Lee, L. V. Toth, Kevin Lacaille, Department of Physics, Particle Physics and Astrophysics, Liverpool John Moores University (LJMU), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA (UMR_8112)), Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), University of Arizona, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), and Université Paris-Seine-Université Paris-Seine-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Milky Way, Continuum (design consultancy), SPIRAL ARMS, FOS: Physical sciences, F800, Astrophysics, 01 natural sciences, ISM: clouds, Luminosity, STAR-FORMATION, CLUMP IDENTIFICATION, symbols.namesake, surveys, 0103 physical sciences, Planck, GOULD BELT SURVEY, 010303 astronomy & astrophysics, James Clerk Maxwell Telescope, Solar and Stellar Astrophysics (astro-ph.SR), QC, QB, Physics, LEGACY SURVEY, Spiral galaxy, stars: formation, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Star formation, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], ATLASGAL, Astronomy and Astrophysics, Galactic plane, 115 Astronomy, Space science, Astrophysics - Astrophysics of Galaxies, CLOUD, submillimetre: ISM, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, [SDU]Sciences of the Universe [physics], GAS, Astrophysics of Galaxies (astro-ph.GA), symbols, MILKY-WAY, [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], COMPLETE SAMPLE
Abstract: We present the first release of the data and compact-source catalogue for the JCMT Large Program SCUBA-2 Continuum Observations of Pre-protostellar Evolution (SCOPE). SCOPE consists of 850-um continuum observations of 1235 Planck Galactic Cold Clumps (PGCCs) made with the Submillimetre Common-User Bolometer Array 2 on the James Clerk Maxwell Telescope. These data are at an angular resolution of 14.4 arcsec, significantly improving upon the 353-GHz resolution of Planck at 5 arcmin, and allowing for a catalogue of 3528 compact sources in 558 PGCCs. We find that the detected PGCCs have significant sub-structure, with 61 per cent of detected PGCCs having 3 or more compact sources, with filamentary structure also prevalent within the sample. A detection rate of 45 per cent is found across the survey, which is 95 per cent complete to Planck column densities of $N_{H_{2}}$ $>$ 5 $\times$ 10$^{21}$ cm$^{-2}$. By positionally associating the SCOPE compact sources with YSOs, the star formation efficiency, as measured by the ratio of luminosity to mass, in nearby clouds is found to be similar to that in the more distant Galactic Plane, with the column density distributions also indistinguishable from each other., 16 pages, 13 figures, 1 table. Accepted for publication in MNRAS
Published: 2019
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13. C2O and C3O in low-mass star-forming regions

Author: A. Jaber Al-Edhari, Francesco Fontani, Maria Elisabetta Palumbo, Ana López-Sepulcre, Leonardo Testi, Emmanuel Caux, R. G. Urso, Nadia Balucani, Rafael Bachiller, Bertrand Lefloch, Sandrine Bottinelli, G. A. Baratta, Paolo Leto, Corrado Trigilio, G. Umana, C. Codella, Cecilia Ceccarelli, Charlotte Vastel, Carla Buemi, ITA, FRA, DEU, ESP, IRQ, University of Turin, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Perugia (UNIPG), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), INAF - Osservatorio Astronomico di Brera (OAB), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Università degli studi di Torino = University of Turin (UNITO), Università degli Studi di Perugia = University of Perugia (UNIPG), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)
Subjects: Astrochemistry, Context (language use), Astrophysics, 01 natural sciences, ISM: abundances, Ion, astrochemistry, ISM: molecules, methods: observational, methods: laboratory: solid state, techniques: spectroscopic, Desorption, Phase (matter), 0103 physical sciences, Irradiation, 010306 general physics, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Molecular cloud, Astronomy and Astrophysics, 13. Climate action, Space and Planetary Science, Chemical physics, [SDU]Sciences of the Universe [physics], [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], Low Mass
Abstract: Context. C2O and C3O belong to the carbon chain oxides family. Both molecules have been detected in the gas phase towards several star-forming regions, and to explain the observed abundances, ion-molecule gas-phase reactions have been invoked. On the other hand, laboratory experiments have shown that carbon chain oxides are formed after energetic processing of CO-rich solid mixtures. Therefore, it has been proposed that they are formed in the solid phase in dense molecular clouds after cosmic ion irradiation of CO-rich icy grain mantles and released in the gas phase after their desorption. Aims. In this work, we contribute to the understanding of the role of both gas-phase reactions and energetic processing in the formation of simple carbon chain oxides that have been searched for in various low-mass star-forming regions. Methods. We present observations obtained with the Noto-32m and IRAM-30 m telescopes towards star-forming regions. We compare these with the results of a gas-phase model that simulates C2O and C3O formation and destruction, and laboratory experiments in which both molecules are produced after energetic processing (with 200 keV protons) of icy grain mantle analogues. Results. New detections of both molecules towards L1544, L1498, and Elias 18 are reported. The adopted gas phase model is not able to reproduce the observed C2O/C3O ratios, while laboratory experiments show that the ion bombardment of CO-rich mixtures produces C2O/C3O ratios that agree with the observed values. Conclusions. Based on the results obtained here, we conclude that the synthesis of both species is due to the energetic processing of CO-rich icy grain mantles. Their subsequent desorption because of non-thermal processes allows the detection in the gas-phase of young star-forming regions. In more evolved objects, the non-detection of both C2O and C3O is due to their fast destruction in the warm gas.
Published: 2019
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14. Astrophysical detections and databases for the mono deuterated species of acetaldehyde CH2DCOH and CH3COD

Author: Roman A. Motiyenko, L. H. Coudert, Charlotte Vastel, Jean-Claude Guillemin, L. Margulès, Emmanuel Caux, Institut des Sciences Moléculaires d'Orsay (ISMO), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 (PhLAM), Université de Lille-Centre National de la Recherche Scientifique (CNRS), Physique Moléculaire aux Interfaces (PMI), Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Université de Lille, Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Astrochemistry, computer.software_genre, 01 natural sciences, chemistry.chemical_compound, ISM molecules, 0103 physical sciences, Molecule, Binary system, 010303 astronomy & astrophysics, ISM abundances, Physics, 010304 chemical physics, Database, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], astrochemistry, Acetaldehyde, Astronomy and Astrophysics, Amplitude, chemistry, Deuterium, Space and Planetary Science, Ophiuchus, line identification, [CHIM.OTHE]Chemical Sciences/Other, computer, Methyl group
Abstract: Context. Detection of deuterated species may provide information on the evolving chemistry in the earliest phases of star-forming regions. For molecules with two isomeric forms of the same isotopic variant, gas-phase and solid-state formation pathways can be differentiated using their abundance ratio. Aims. Spectroscopic databases for astrophysical purposes are built for the two mono deuterated isomeric species CH2DCOH and CH3COD of the complex organic molecule acetaldehyde. These databases can be used to search and detect these two species in astrophysical surveys, retrieving their column density and therefore abundances. Methods. Submillimeter wave and terahertz transitions were measured for mono deuterated acetaldehyde CH2DCOH which is a non-rigid species displaying internal rotation of its asymmetrical CH2D methyl group. An analysis of a dataset consisting of previously measured microwave data and the newly measured transition was carried out with a model accounting for the large amplitude torsion. Results. The frequencies of 2556 transitions are reproduced with a unitless standard deviation of 2.3 yielding various spectroscopic constants. Spectroscopic databases for astrophysical purposes were built for CH2DCOH using the results of the present analysis and for CH3COD using the results of a previous spectroscopic investigation. These two species were both searched for and are detected toward a low-mass star-forming region. Conclusions. We report the first detection of CH2DCOH (93 transitions) and the detection of CH3COD (43 transitions) species in source B of the IRAS 16293−2422 young stellar binary system located in the ρ Ophiuchus cloud region, using the publicly available ALMA Protostellar Interferometric Line Survey.
Published: 2019
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15. Isocyanogen formation in the cold interstellar medium

Author: Bertrand Lefloch, Valentine Wakelam, Jean-Christophe Loison, Charlotte Vastel, Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Moléculaires (ISM), Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), AMOR 2019, Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), and Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1 (UB)-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Astrochemistry, 010504 meteorology & atmospheric sciences, molecular data, Cyanogen, Abundance (chemistry), Analytical chemistry, FOS: Physical sciences, chemistry.chemical_element, Context (language use), Astrophysics, 01 natural sciences, 7. Clean energy, chemistry.chemical_compound, Metastability, 0103 physical sciences, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], astrochemistry, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Nitrogen, Interstellar medium, molecular processes, Astrophysics - Solar and Stellar Astrophysics, chemistry, 13. Climate action, Space and Planetary Science, [SDU]Sciences of the Universe [physics], radiative transfer, Astrophysics of Galaxies (astro-ph.GA), [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], Chemical network, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], line: identification
Abstract: Cyanogen (NCCN) is the simplest member of the dicyanopolyynes group, and has been proposed as a major source of the CN radical observed in cometary atmospheres. Although not detected through its rotational spectrum in the cold interstellar medium, this very stable species is supposed to be very abundant. The chemistry of cyanogen in the cold interstellar medium can be investigated through its metastable isomer, CNCN (isocyanogen). Its formation may provide a clue on the widely abundant CN radical observed in cometary atmospheres. We performed an unbiased spectral survey of the L1544 proto-typical prestellar core, using the IRAM-30m and have analysed, for this paper, the nitrogen chemistry that leads to the formation of isocyanogen. We report on the first detection of CNCN, NCCNH+, C3N, CH3CN, C2H3CN, and H2CN in L1544. We built a detailed chemical network for NCCN/CNCN/HC2N2+ involving all the nitrogen bearing species detected (CN, HCN, HNC, C3N, CNCN, CH3CN, CH2CN, HCCNC, HC3N, HNC3, H2CN, C2H3CN, HCNH+, HC3NH+) and the upper limits on C4N, C2N. The main cyanogen production pathways considered in the network are the CN + HNC and N + C3N reactions. The comparison between the observations of the nitrogen bearing species and the predictions from the chemical modelling shows a very good agreement, taking into account the new chemical network. The expected cyanogen abundance is greater than the isocyanogen abundance by a factor of 100. Although cyanogen cannot be detected through its rotational spectrum, the chemical modelling predicts that it should be abundant in the gas phase and hence might be traced through the detection of isocyanogen. It is however expected to have a very low abundance on the grain surfaces compared to HCN., accepted in A&A (March 2019)
Published: 2019
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16. Multi-scale analysis of the Monoceros OB 1 star-forming region: II. Colliding filaments in the Monoceros OB1 molecular cloud

Author: David Cornu, David Eden, Mika Saajasto, Jinhua He, Charlotte Vastel, Chang Won Lee, D. Alina, Elisabetta R. Micelotta, Kee-Tae Kim, Yasuo Doi, Alessio Traficante, Sarolta Zahorecz, Ke Wang, Sung-ju Kang, Mark G. Rawlings, V. M. Pelkonen, D. J. Marshall, J. Montillaud, Isabelle Ristorcelli, Mika Juvela, Patrick M. Koch, Archana Soam, Johanna Malinen, L. Viktor Tóth, Tie Liu, Rebeka Bögner, Patricio Sanhueza, Univers, Transport, Interfaces, Nanostructures, Atmosphère et environnement, Molécules (UMR 6213) (UTINAM), Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), University of Helsinki, Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Yunnan Observatories, Chinese Academy of Sciences [Changchun Branch] (CAS), UNIV CHILI, Korea Astronomy and Space Science Institute (KASI), Okayama University, Liverpool John Moores University (LJMU), Academia Sinica Institute of Astronomy and Astrophysics (ASIAA), Academia Sinica, University of Hawai'i [Hilo], Tokyo University of Science [Tokyo], University of Cologne, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Department of Physics [Helsinki], Falculty of Science [Helsinki], University of Helsinki-University of Helsinki, Eötvös Loránd University (ELTE), European Southern Observatory (ESO), This work was supported by the Programme National 'Physique et Chimie du Milieu Interstellaire' (PCMI) of CNRS/INSU with INC/INP co-funded by CEA and CNES., funding from the 'Soutien à la recherche de l’observatoire' by the OSU THETA., The project leading to this publication has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 730 562 [RadioNet]., Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Helsingin yliopisto = Helsingfors universitet = University of Helsinki, Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Helsingin yliopisto = Helsingfors universitet = University of Helsinki-Helsingin yliopisto = Helsingfors universitet = University of Helsinki, Department of Physics, Particle Physics and Astrophysics, Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), and Okayama University [Okayama]
Subjects: Infrared, LINE, FOS: Physical sciences, M QUIET CLUMPS, DUST, Astrophysics, HERBIG-HARO FLOWS, MASS, POLARIMETRY, 01 natural sciences, ISM: clouds, MAGNETIC-FIELDS, Protein filament, 0103 physical sciences, Protostar, 010303 astronomy & astrophysics, QC, QB, Physics, stars: formation, 010308 nuclear & particles physics, Velocity gradient, Star formation, Molecular cloud, Astronomy and Astrophysics, 115 Astronomy, Space science, Collision, Astrophysics - Astrophysics of Galaxies, GAS, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), PROTOCLUSTERS, Vector field, EMISSION, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: We started a multi-scale analysis of G202.3+2.5, an intertwined filamentary region of Monoceros OB1. In Paper I, we examined the distributions of dense cores and protostars and found enhanced star formation (SF) activity in the junction region of the filaments. In this second paper, we aim to unveil the connections between the core and filament evolutions, and between the filament dynamics and the global evolution of the cloud. We characterise the gas dynamics and energy balance using Herschel and WISE observations and molecular tracers observed with the IRAM 30m and TRAO 14m telescopes. The velocity field of the cloud is examined and velocity-coherent structures are put in perspective with the cloud environment. Two main velocity components (VCs) are revealed, well separated in the north and merged around the location of intense N2H+ emission where Paper I found the peak of SF activity. The relative position of the two VCs along the sightline, and the velocity gradient in N2H+ emission imply that the VCs have been undergoing collision for ~10^5 yrs. The dense gas where N2H+ is detected is interpreted as the compressed region between the two filaments, which corresponds to a high mass inflow rate of ~1e-3 Msun/yr and possibly leads to an increase in its SF efficiency. We identify a protostar in the junction region that possibly powers two crossed intermittent outflows. We show that the HII region around the nearby cluster NCG 2264 is still expanding and its role in the collision is examined. However, we cannot rule out the idea that the collision arises mostly from the global collapse of the cloud. The (sub-)filament-scale observables examined in this paper reveal a collision between G202.3+2.5 sub-structures and its probable role in feeding the cores in the junction region. One must now characterise the cloud morphology, its fragmentation, and magnetic field, all at high resolution., Comment: A&A, in press; IRAM and TRAO data cubes will be available at CDS
Published: 2019
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17. Molecular complexity in pre-stellar cores: a 3 mm-band study of L183 and L1544

Author: Paola Caselli, Barbara M. Giuliano, Charlotte Vastel, Valerio Lattanzi, Anton Vasyunin, Jorma Harju, Luca Bizzocchi, Particle Physics and Astrophysics, Department of Physics, Lattanzi V., Bizzocchi L., Vasyunin A.I., Harju J., Giuliano B.M., Vastel C., and Caselli P.
Subjects: molecular data, 010504 meteorology & atmospheric sciences, ENVIRONMENTAL CONDITIONS, ISM: molecule, Astrophysics, 01 natural sciences, ASTROPHYSICAL INTEREST, chemistry.chemical_compound, Molecular processe, IDENTIFICATION [LINE], Emission spectrum, CHEMICAL DIFFERENTIATION, 010303 astronomy & astrophysics, Chemical composition, Physics, CHEMICAL ANALYSIS, EXTERNAL CONDITIONS, LABORATORY DETECTION, ISOLATED STAR-FORMATION, ISM: molecules, DEUTERIUM FRACTIONATION, MICROWAVE-SPECTRA, EXCITATION TEMPERATURE, line: identification, INTERSTELLAR RADIATION, OXYGEN-CONTAINING SPECIES, chemistry.chemical_element, Context (language use), INITIAL CONDITIONS, PARABOLIC ANTENNAS, 0103 physical sciences, MOLECULAR COMPLEXITY, Molecule, 0105 earth and related environmental sciences, radio lines: ISM, CHEMICAL COMPOSITIONS, Star formation, Molecular cloud, ISM [RADIO LINES], CARBON MONOXIDE, Astronomy and Astrophysics, MOLECULAR DATA, 115 Astronomy, Space science, LAMB-DIP SPECTRUM, molecular processes, chemistry, 13. Climate action, Space and Planetary Science, MOLECULES [ISM], HYPERFINE-STRUCTURE, Carbon, ROTATIONAL SPECTRUM, STARS, SURVEYS, SUBMILLIMETER-WAVE SPECTRUM, MOLECULAR PROCESSES, Carbon monoxide
Abstract: Context. Pre-stellar cores (PSCs) are units of star formation. Besides representing early stages of the dynamical evolution leading to the formation of stars and planets, PSCs also provide a substrate for incipient chemical complexity in the interstellar space. Aims. Our aim is to understand the influence of external conditions on the chemical composition of PSCs. For this purpose, we compared molecular column densities in two typical PSCs, L183 and L1544, which are embedded in different environments. Methods. A single-pointing survey of L183 at λ = 3 mm was conducted using the IRAM 30-m single-dish antenna. This led to the detection of more than 100 emission lines from 46 molecular species. The molecular column densities and excitation temperatures derived from these lines were compared to the corresponding parameters in L1544. The data for L1544 were obtained from literature or publicly available surveys, and they were analysed using the same procedure as adopted for L183. An astrochemical model, previously developed for the interpretation of organic molecule emissions towards the methanol peak of L1544, was used to interpret the combined data. Results. Our analysis reveals clear chemical differences between the two PSCs. While L1544 is richer in carbon-bearing species, in particular carbon chains, oxygen-containing species are generally more abundant in L183. The results are well-reproduced by our chemical model. Conclusions. The observed chemical differentiation between the two PSCs is caused by the different environmental conditions: the core of L183 is deeply buried in the surrounding cloud, whereas L1544 lies close to the edge of the Taurus Molecular Cloud. The obscuration of L183 from the interstellar radiation field (ISRF) allows the carbon atoms to be locked in carbon monoxide, which ultimately leads to a large abundance of O-bearing species. In contrast, L1544, being more affected by the ISRF, can keep a fraction of carbon in atomic form, which is needed for the production of carbon chains. © V. Lattanzi et al. 2020. Latvijas ZinÄ tnes Padome: lzp-2018/1-0170 for fruitful comments on the SO2 chemistry. Evelyne Roueff is also gratefully acknowledged for discussions on reaction rates of some complex organic molecules in our model. We also thank Elena Redaelli for providing the L1544 SPIRE density profile. The work by A.I.V. is supported by Latvian Council of Science via the Project lzp-2018/1-0170.
Published: 2020
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18. The nitrogen isotopic ratio of HC3N towards the L1544 prestellar core

Author: P. Hily-Blant, Charlotte Vastel, Rafael Bachiller, Alexandre Faure, Victor de Souza Magalhaes, Bertrand Lefloch, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Univ Toulouse UPS, Ctr Etud Spatiale Rayonnements, F-31062 Toulouse 9, France, and Centre Etud Spatiale Rayonnements Toulouse
Subjects: Physics, Astrochemistry, 010504 meteorology & atmospheric sciences, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Interstellar cloud, FOS: Physical sciences, Astronomy and Astrophysics, Protoplanetary disk, 01 natural sciences, Astrophysics - Astrophysics of Galaxies, Interstellar medium, 13. Climate action, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Product (mathematics), Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Protostar, Isotopologue, Atomic physics, 010303 astronomy & astrophysics, Hyperfine structure, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: The origin of the heavily fractionated reservoir of nitrogen in comets remains an issue in the theory of their formation and hence of the solar system. Whether the fractionated reservoir traced by comets is inherited from the interstellar cloud or is the product of processes taking place in the protostar, or in the protoplanetary disk, remains unclear. So far, observations of nitrogen isotopic ratios in protostars or prestellar cores have not securely identified such a fractionated reservoir owing to the intrinsic difficulty of direct isotopic ratios measurements. In this article, we report the detection of 5 rotational lines of \ce{HC3N}, {including the weaker components of the hyperfine multiplets}, and two rotational lines of its $^{15}$N isotopologue, towards the L1544 prestellar core. Based on a MCMC/non-LTE multi-line analysis at the hyperfine level, we derive the column densities of \ce{HC3N} ($8.0\pm0.4\tdix{13}$\cc) and \ce{HC3^{15}N} ($2.0\pm0.4\tdix{11}$\cc) and derive an isotopic ratio of 400$\pm$20(1$\sigma$). This value suggests that \ce{HC3N} is slightly depleted in $^{15}$N in L1544 with respect to the elemental $^{14}$N/$^{15}$N ratio {of $\approx$330} in the present-day local interstellar medium. Our study also stresses the need for radiative calculations at the hyperfine level. Finally, the comparison of the derived ratio with those obtained in CN and HCN in the same core seems to favor CN+C$_2$H$_2$ as the dominant formation route to HC$_3$N. However, uncertainties in the isotopic ratios preclude definitive conclusions., Comment: Accepted for publication in MNRAS
Published: 2018
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19. Astrochemical evolution along star formation: overview of the IRAM Large Program ASAI

Author: E. Mendoza, Emmanuel Caux, José Cernicharo, Cécile Favre, Serena Viti, Kento Yoshida, Charlotte Vastel, Ana López-Sepulcre, Sylvie Cabrit, A. Fuente, E. Bianchi, Rafael Bachiller, Bertrand Lefloch, E. Roueff, Jonathan Holdship, Linda Podio, M. González-García, Cecilia Ceccarelli, Satoshi Yamamoto, T. Monfredini, Claudio Codella, A. I. Gómez-Ruiz, Nami Sakai, Nuria Marcelino, D. Quénard, Claudine Kahane, J. Ospina-Zamudio, Heloisa M. Boechat-Roberty, Mario Tafalla, Heidy M Quitián-Lara, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Instituto de Ciencia de Materiales de Madrid (ICMM), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), foreign laboratories (FL), CERN [Genève], Univ Toulouse UPS, Ctr Etud Spatiale Rayonnements, F-31062 Toulouse 9, France, Centre Etud Spatiale Rayonnements Toulouse, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Instituto de Radio Astronomía Milimétrica, University College of London [London] (UCL), Centro de Investigaciones Energéticas Medioambientales y Tecnológicas [Madrid] (CIEMAT), INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA (UMR_8112)), Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Institut de biologie et chimie des protéines [Lyon] (IBCP), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Division of Clinical and Molecular Genetics, Shinshu University Hospital, Institut de Mathématiques de Jussieu (IMJ), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astronomico di Bologna (OABO), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Consejo Superior de Investigaciones Científicas [Spain] (CSIC), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP)
Subjects: Physics, [PHYS]Physics [physics], Solar System, Astrochemistry, 010308 nuclear & particles physics, Star formation, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, 01 natural sciences, Astrophysics - Astrophysics of Galaxies, Article, Stars, 13. Climate action, Space and Planetary Science, Asteroid, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Formation and evolution of the Solar System, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, Chemical composition, ComputingMilieux_MISCELLANEOUS, Line (formation)
Abstract: Evidence is mounting that the small bodies of our Solar System, such as comets and asteroids, have at least partially inherited their chemical composition from the first phases of the Solar System formation. It then appears that the molecular complexity of these small bodies is most likely related to the earliest stages of star formation. It is therefore important to characterize and to understand how the chemical evolution changes with solar-type protostellar evolution. We present here the Large Program "Astrochemical Surveys At IRAM" (ASAI). Its goal is to carry out unbiased millimeter line surveys between 80 and 272 GHz of a sample of ten template sources, which fully cover the first stages of the formation process of solar-type stars, from prestellar cores to the late protostellar phase. In this article, we present an overview of the surveys and results obtained from the analysis of the 3 mm band observations. The number of detected main isotopic species barely varies with the evolutionary stage and is found to be very similar to that of massive star-forming regions. The molecular content in O- and C- bearing species allows us to define two chemical classes of envelopes, whose composition is dominated by either a) a rich content in O-rich complex organic molecules, associated with hot corino sources, or b) a rich content in hydrocarbons, typical of Warm Carbon Chain Chemistry sources. Overall, a high chemical richness is found to be present already in the initial phases of solar-type star formation., 19 pages, 7 figures, 5 Tables
Published: 2018
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20. Sulphur chemistry in the L1544 pre-stellar core

Author: Thomas H. G. Vidal, Valentine Wakelam, Rafael Bachiller, R. Le Gal, A. Andrianasolo, Charlotte Vastel, Cecilia Ceccarelli, Bertrand Lefloch, D. Quénard, Paola Caselli, Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), AMOR 2018, Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie ( IRAP ), Université Paul Sabatier - Toulouse 3 ( UPS ) -Observatoire Midi-Pyrénées ( OMP ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire d'Astrophysique de Bordeaux [Pessac] ( LAB ), Université de Bordeaux ( UB ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Bordeaux ( UB ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), Institut de Planétologie et d'Astrophysique de Grenoble ( IPAG ), Observatoire des Sciences de l'Univers de Grenoble ( OSUG ), Université Joseph Fourier - Grenoble 1 ( UJF ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Grenoble Alpes ( UGA ) -Université Joseph Fourier - Grenoble 1 ( UJF ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Grenoble Alpes ( UGA ) -Centre National de la Recherche Scientifique ( CNRS ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), and Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])
Subjects: Physics, [ PHYS.ASTR.SR ] Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Line-of-sight, Astrochemistry, 010308 nuclear & particles physics, Thermal desorption, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, [ PHYS.ASTR.CO ] Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], 01 natural sciences, Astrophysics - Astrophysics of Galaxies, Ion, Isotopomers, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Pre-stellar core, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Abundance (ecology), Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Radiative transfer, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR)
Abstract: The L1544 pre-stellar core has been observed as part of the ASAI IRAM 30m Large Program as well as follow-up programs. These observations have revealed the chemical richness of the earliest phases of low-mass star-forming regions. In this paper we focus on the twenty-one sulphur bearing species (ions, isotopomers and deuteration) that have been detected in this spectral-survey through fifty one transitions: CS, CCS, C3S, SO, SO2, H2CS, OCS, HSCN, NS, HCS+, NS+ and H2S. We also report the tentative detection (4 {\sigma} level) for methyl mercaptan (CH3SH). LTE and non-LTE radiative transfer modelling have been performed and we used the nautilus chemical code updated with the most recent chemical network for sulphur to explain our observations. From the chemical modelling we expect a strong radial variation for the abundances of these species, which mostly are emitted in the external layer where non thermal desorption of other species has previously been observed. We show that the chemical study cannot be compared to what has been done for the TMC-1 dark cloud, where the abundance is supposed constant along the line of sight, and conclude that a strong sulphur depletion is necessary to fully reproduce our observations of the prototypical pre-stellar core L1544., Comment: Accepted in MNRAS 2018 May 15. Received 2018 May 15; in original form 2018 January 30
Published: 2018
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21. Deuterium and $^{15}$N fractionation in N$_2$H$^+$ during the formation of a Sun-like star

Author: Claudio Codella, Cecilia Ceccarelli, J. Soldateschi, Francesco Fontani, M. De Simone, Charlotte Vastel, Emmanuel Caux, Ana López-Sepulcre, Bertrand Lefloch, Rafael Bachiller, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)
Subjects: 010504 meteorology & atmospheric sciences, Chemical models, Star (game theory), FOS: Physical sciences, Fractionation, ISM: clouds, 01 natural sciences, TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY, Phase (matter), 0103 physical sciences, Isotopologue, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), 0105 earth and related environmental sciences, Physics, radio lines: ISM, stars: formation, Star formation, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, ISM: molecules, Deuterium, Astrophysics - Solar and Stellar Astrophysics, [SDU]Sciences of the Universe [physics], 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Atomic physics
Abstract: Although chemical models predict that the deuterium fractionation in N$_2$H$^+$ is a good evolutionary tracer in the star formation process, the fractionation of nitrogen is still a poorly understood process. Recent models have questioned the similar evolutionary trend expected for the two fractionation mechanisms in N$_2$H$^+$, based on a classical scenario in which ion-neutral reactions occurring in cold gas should have caused an enhancement of the abundance of N$_2$D$^+$, $^{15}$NNH$^+$, and N$^{15}$NH$^+$. In the framework of the ASAI IRAM-30m large program, we have investigated the fractionation of deuterium and $^{15}$N in N$_2$H$^+$ in the best known representatives of the different evolutionary stages of the Sun-like star formation process. The goal is to ultimately confirm (or deny) the classical "ion-neutral reactions" scenario that predicts a similar trend for D and $^{15}$N fractionation. We do not find any evolutionary trend of the $^{14}$N/$^{15}$N ratio from both the $^{15}$NNH$^+$ and N$^{15}$NH$^+$ isotopologues. Therefore, our findings confirm that, during the formation of a Sun-like star, the core evolution is irrelevant in the fractionation of $^{15}$N. The independence of the $^{14}$N/$^{15}$N ratio with time, found also in high-mass star-forming cores, indicates that the enrichment in $^{15}$N revealed in comets and protoplanetary disks is unlikely to happen at core scales. Nevertheless, we have firmly confirmed the evolutionary trend expected for the H/D ratio, with the N$_2$H$^+$/N$_2$D$^+$ ratio decreasing before the pre-stellar core phase, and increasing monotonically during the protostellar phase. We have also confirmed clearly that the two fractionation mechanisms are not related., 9 pages, 2 figures, accepted for publication in MNRAS
Published: 2018
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22. Discovery of the Ubiquitous Cation NS+ in Space Confirmed by Laboratory Spectroscopy

Author: José Cernicharo, Bertrand Lefloch, Charlotte Vastel, Marcelino Agúndez, Laurent Margulès, Nuria Marcelino, Evelyne Roueff, Emmanuel Caux, Belén Tercero, S. Bailleux, Rafael Bachiller, Ministerio de Economía y Competitividad (España), European Commission, Centre National D'Etudes Spatiales (France), Agence Nationale de la Recherche (France), Cernicharo, José [0000-0002-3518-2524], Bachiller, R. [0000-0002-5331-5386], Tercero, B. [0000-0002-4782-5259], Instituto de Ciencia de Materiales de Madrid (ICMM), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 (PhLAM), Université de Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA (UMR_8112)), Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), INAF - Osservatorio Astronomico di Bologna (OABO), Istituto Nazionale di Astrofisica (INAF), Univ Toulouse UPS, Ctr Etud Spatiale Rayonnements, F-31062 Toulouse 9, France, Centre Etud Spatiale Rayonnements Toulouse, Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Cernicharo, José, Bachiller, R., Tercero, B., Consejo Superior de Investigaciones Científicas [Spain] (CSIC), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Centre d'étude spatiale des rayonnements (CESR), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)
Subjects: Line: identification, FOS: Physical sciences, 7. Clean energy, 01 natural sciences, Molecular physics, ISM: clouds, Ab initio quantum chemistry methods, 0103 physical sciences, Molecule, identification [Line], Spectroscopy, Spin (physics), 010303 astronomy & astrophysics, Hyperfine structure, Radio lines: ISM, Astrophysics::Galaxy Astrophysics, ComputingMilieux_MISCELLANEOUS, Physics, [PHYS]Physics [physics], 010304 chemical physics, Molecular data, Molecular cloud, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, ISM [Radio lines], 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Rotational spectroscopy, Ground state, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], clouds [ISM]
Abstract: 7 pags., 3 figs., 2 tabs., We report the detection in space of a new molecular species that has been characterized spectroscopically and fully identified from astrophysical data. The observations were carried out with the IRAM 30 m telescope. The molecule is ubiquitous as its J = → 2 1 transition has been found in cold molecular clouds, prestellar cores, and shocks. However, it is not found in the hot cores of Orion-KL and in the carbon-rich evolved star IRC+10216. Three rotational transitions in perfect harmonic relation J = 2 3 5 have been identified in the prestellar core B1b. The molecule has a 1S electronic ground state and its J = → 2 1 transition presents the hyperfine structure characteristic of a molecule containing a nucleus with spin 1. A careful analysis of possible carriers shows that the best candidate is NS+. The derived rotational constant agrees within 0.3%-0.7% with ab initio calculations. NS+ was also produced in the laboratory to unambiguously validate the astrophysical assignment. The observed rotational frequencies and determined molecular constants confirm the discovery of the nitrogen sulfide cation in space. The chemistry of NS+ and related nitrogen-bearing species has been analyzed by means of a time-dependent gas-phase model. The model reproduces well the observed NS/NS+ abundance ratio, in the range 30-50, and indicates that NS+ is formed by reactions of the neutral atoms N and S with the cations SH+ and NH+, respectively., We thank funding support from Spanish MINECO (grants AYA2012-32032, AYA2016-75066-C2-1-P, CSD2009-00038, and RyC-2014-16277) and from European Research Council (grant ERC-2013-SyG 610256, NANOCOSMOS). This work was also supported by the Programme National PCMI CEA and CNES, and the French National Research Agency (ANR-13-BS05-0008-02 “IMOLABS”).
Published: 2018
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23. Seeds of Life in Space (SOLIS). III. Zooming Into the Methanol Peak of the Prestellar Core L1544

Author: Jonathan Holdship, Ana Chacón-Tanarro, Ana López-Sepulcre, Vianney Taquet, Claudio Codella, J. Laas, D. Quenard, Francesco Fontani, P. Hily-Blant, Ali Jaber Al-Edhari, Cécile Favre, Linda Podio, Serena Viti, Nami Sakai, Yoko Oya, Leonardo Testi, Jaime E. Pineda, Patrice Theulé, J. Ospina-Zamudio, François Dulieu, Luca Bizzocchi, Emmanuel Caux, Albert Rimola, E. Bianchi, Roberto Neri, Nadia Balucani, Anton Vasyunin, Anna Punanova, Izaskun Jiménez-Serra, Rumpa Choudhury, Sandrine Bottinelli, Rafael Bachiller, Bertrand Lefloch, Piero Ugliengo, Claudine Kahane, Andy Pon, S. Spezzano, Satoshi Yamamoto, Felipe O. Alves, Cecilia Ceccarelli, Ian R. Sims, Siyi Feng, Charlotte Vastel, Paola Caselli, Ural Federal University [Ekaterinburg] (UrFU), Max Planck Institute for Extraterrestrial Physics (MPE), Max-Planck-Gesellschaft, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), INAF - Osservatorio Astronomico di Brera (OAB), Istituto Nazionale di Astrofisica (INAF), Queen Mary University of London (QMUL), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), University of Western Ontario (UWO), INAF - Osservatorio Astrofisico di Arcetri (OAA), University of Electro-Communications [Tokyo] (UEC), Università degli Studi di Perugia (UNIPG), Università degli Studi di Firenze = University of Florence [Firenze] (UNIFI), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA (UMR_8112)), Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Universitat Autònoma de Barcelona (UAB), RIKEN - Institute of Physical and Chemical Research [Japon] (RIKEN), Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Universiteit Leiden [Leiden], Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Ortopedia e Medicina del Lavoro, Università degli Studi di Torino, 10126 Turin, European Research Council (ERC) [PALs 320620], CITA National Fellowship, STFC [ST/L004801, ST/M004139], STFC through an Ernest Rutherford Fellowship, ERC [DOC 741002], Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Perugia = University of Perugia (UNIPG), Università degli Studi di Firenze = University of Florence (UniFI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Universiteit Leiden, Università degli studi di Torino = University of Turin (UNITO), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Firenze [Firenze], PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), and Universitat Autònoma de Barcelona [Barcelona] (UAB)
Subjects: ISM kinematics and dynamics, ISM individual objects (L1544), radio lines ISM, Thermodynamic equilibrium, Continuum (design consultancy), FOS: Physical sciences, ISM: clouds, 01 natural sciences, Molecular physics, ISM molecules, 0103 physical sciences, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), ISM: kinematics and dynamics, Physics, [PHYS]Physics [physics], ISM: individual objects (L1544), ISM: molecules, radio lines: ISM, stars: formation, Astronomy and Astrophysics, Space and Planetary Science, Accretion (meteorology), 010308 nuclear & particles physics, Velocity dispersion, Rotational temperature, Static core, Astrophysics - Astrophysics of Galaxies, stars formation, Core (optical fiber), ISM clouds, Astrophysics - Solar and Stellar Astrophysics, Astrophysics of Galaxies (astro-ph.GA), astrochimica, Order of magnitude
Abstract: Towards the pre-stellar core L1544, the methanol (CH$_3$OH) emission forms an asymmetric ring around the core centre, where CH$_3$OH is mostly in solid form, with a clear peak 4000~au to the north-east of the dust continuum peak. As part of the NOEMA Large Project SOLIS (Seeds of Life in Space), the CH$_3$OH peak has been spatially resolved to study its kinematics and physical structure and to investigate the cause behind the local enhancement. We find that methanol emission is distributed in a ridge parallel to the main axis of the dense core. The centroid velocity increases by about 0.2~km~s$^{-1}$ and the velocity dispersion increases from subsonic to transonic towards the central zone of the core, where the velocity field also shows complex structure. This could be indication of gentle accretion of material onto the core or interaction of two filaments, producing a slow shock. We measure the rotational temperature and show that methanol is in local thermodynamic equilibrium (LTE) only close to the dust peak, where it is significantly depleted. The CH$_3$OH column density, $N_{tot}({\rm CH_3OH})$, profile has been derived with non-LTE radiative transfer modelling and compared with chemical models of a static core. The measured $N_{tot}({\rm CH_3OH})$ profile is consistent with model predictions, but the total column densities are one order of magnitude lower than those predicted by models, suggesting that the efficiency of reactive desorption or atomic hydrogen tunnelling adopted in the model may be overestimated; or that an evolutionary model is needed to better reproduce methanol abundance., 19 pages, 18 figures. Accepted by ApJ
Published: 2018
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24. Seeds of Life in Space (SOLIS). II. Formamide in protostellar shocks: Evidence for gas-phase formation

Author: Izaskun Jiménez-Serra, Ana Chacón-Tanarro, Claudine Kahane, Andy Pon, R. Neri, Yoko Oya, Patrice Theulé, Leonardo Testi, Audrey Coutens, Paola Caselli, Charlotte Vastel, Serena Viti, François Dulieu, Jaime E. Pineda, R. Choudhury, P. Hily-Blant, J. Ospina, Fanny Vazart, Vincenzo Barone, Ana López-Sepulcre, Ian R. Sims, Laurent Wiesenfeld, Claudio Codella, Anna Punanova, Sandrine Bottinelli, Vianney Taquet, Francesco Fontani, Jacob C. Laas, A. Jaber Al-Edhari, Linda Podio, Cecilia Ceccarelli, Satoshi Yamamoto, Nami Sakai, Felipe O. Alves, Rafael Bachiller, Emmanuel Caux, S. Spezzano, D. Quénard, Nadia Balucani, Siyi Feng, Cécile Favre, Luca Bizzocchi, Cristina Puzzarini, Bertrand Lefloch, Piero Ugliengo, Anton Vasyunin, Jonathan Holdship, Dimitrios Skouteris, Albert Rimola, E. Bianchi, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), Università degli Studi di Perugia (UNIPG), INAF - Osservatorio Astronomico di Brera (OAB), Southern University of Science and Technology [Shenzhen] (SUSTech), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Queen Mary University of London (QMUL), University College of London [London] (UCL), ESAB, Universitad polytecnica de Cataluna, University of Western Ontario (UWO), Max Planck Institute for Extraterrestrial Physics (MPE), Max-Planck-Gesellschaft, Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), departament de Quimica, Universitat Autònoma de Barcelona [Barcelona] (UAB), RIKEN - Institute of Physical and Chemical Research [Japon] (RIKEN), Scuola Normale Superiore di Pisa (SNS), European Southern Observatory (ESO), Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Università degli studi di Torino (UNITO), Codella, C., Ceccarelli, C., Caselli, P., Balucani, N., Barone, V., Fontani, F., Lefloch, B., Podio, L., Viti, S., Feng, S., Bachiller, R., Bianchi, E., Dulieu, F., Jiménez-Serra, I., Holdship, J., Neri, R., Pineda, J.E., Pon, A., Sims, I., Spezzano, S., Vasyunin, A.I., Alves, F., Bizzocchi, L., Bottinelli, S., Caux, E., Chacón-Tanarro, A., Choudhury, R., Coutens, A., Favre, C., Hily-Blant, P., Kahane, C., Jaber Al-Edhari, A., Laas, J., López-Sepulcre, A., Ospina, J., Oya, Y., Punanova, A., Puzzarini, C., Quenard, D., Rimola, A., Sakai, N., Skouteris, D., Taquet, V., Testi, L., Theulé, P., Ugliengo, P., Vastel, C., Vazart, F., Wiesenfeld, L., Yamamoto, S., Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Università degli Studi di Perugia = University of Perugia (UNIPG), Southern University of Science and Technology (SUSTech), LERMA Cergy (LERMA), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA (UMR_8112)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris-Seine-Université Paris-Seine-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Universitat Autònoma de Barcelona (UAB), Università degli studi di Torino = University of Turin (UNITO), Pineda, J. E., Vasyunin, A. I., Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Cergy Pontoise (UCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)
Subjects: Formamide, Abundance (chemistry), Direct evidence, Stars: formation, FOS: Physical sciences, Context (language use), Astrophysics, ISM: molecule, 01 natural sciences, chemistry.chemical_compound, 0103 physical sciences, Protostar, molecule [ISM], 010303 astronomy & astrophysics, ISM: jets and outflow, formation [Stars], ComputingMilieux_MISCELLANEOUS, Line (formation), Earth and Planetary Astrophysics (astro-ph.EP), ISM: individual objects: L1157-B1, ISM: jets and outflows, ISM: molecules, Astronomy and Astrophysics, Space and Planetary Science, Physics, [PHYS]Physics [physics], 010308 nuclear & particles physics, jets and outflow [ISM], individual objects: L1157-B1 [ISM], Astronomy and Astrophysic, Stars, chemistry, Millimeter, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Earth and Planetary Astrophysics
Abstract: Context: Modern versions of the Miller-Urey experiment claim that formamide (NH$_2$CHO) could be the starting point for the formation of metabolic and genetic macromolecules. Intriguingly, formamide is indeed observed in regions forming Solar-type stars as well as in external galaxies. Aims: How NH$_2$CHO is formed has been a puzzle for decades: our goal is to contribute to the hotly debated question of whether formamide is mostly formed via gas-phase or grain surface chemistry. Methods: We used the NOEMA interferometer to image NH$_2$CHO towards the L1157-B1 blue-shifted shock, a well known interstellar laboratory, to study how the components of dust mantles and cores released into the gas phase triggers the formation of formamide. Results: We report the first spatially resolved image (size $\sim$ 9", $\sim$ 2300 AU) of formamide emission in a shocked region around a Sun-like protostar: the line profiles are blueshifted and have a FWHM $\simeq$ 5 km s$^{-1}$. A column density of $N_{\rm NH_2CHO}$ = 8 $\times$ 10$^{12}$ cm$^{-1}$, and an abundance (with respect to H-nuclei) of 4 $\times$ 10$^{-9}$ are derived. We show a spatial segregation of formamide with respect to other organic species. Our observations, coupled with a chemical modelling analysis, indicate that the formamide observed in L1157-B1 is formed by gas-phase chemical process, and not on grain surfaces as previously suggested. Conclusions: The SOLIS interferometric observations of formamide provide direct evidence that this potentially crucial brick of life is efficiently formed in the gas-phase around Sun-like protostars., 7 pages, 1 table, 5 figures, A&A Letters, in press
Published: 2017
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25. High spectral resolution observations of HNC3 and HCCNC in the L1544 prestellar core

Author: Kentarou Kawaguchi, D. Quénard, Masatoshi Ohishi, H S P Müller, Bertrand Lefloch, Charlotte Vastel, Rafael Bachiller, Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), and Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])
Subjects: Astrochemistry, 010504 meteorology & atmospheric sciences, FOS: Physical sciences, Astrophysics, 01 natural sciences, ISM: abundances, chemistry.chemical_compound, Abundance (ecology), 0103 physical sciences, Cyanoacetylene, Spectral resolution, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Physics, astrochemistry, Late stage, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, ISM: molecules, Pre-stellar core, chemistry, Space and Planetary Science, ISM: individual objects: L1544, [SDU]Sciences of the Universe [physics], Astrophysics of Galaxies (astro-ph.GA), Millimeter, line: identification
Abstract: HCCNC and HNC3 are less commonly found isomers of cyanoacetylene, HC3N, a molecule that is widely found in diverse astronomical sources. We want to know if HNC3 is present in sources other than the dark cloud TMC-1 and how its abundance is relative to that of related molecules. We used the ASAI unbiased spectral survey at IRAM 30m towards the prototypical prestellar core L1544 to search for HNC3 and HCCNC which are by-product of the HC3NH+ recombination, previously detected in this source. We performed a combined analysis of published HNC3 microwave rest frequencies with thus far unpublished millimeter data because of issues with available rest frequency predictions. We determined new spectroscopic parameters for HNC3, produced new predictions and detected it towards L1544. We used a gas-grain chemical modelling to predict the abundances of N-species and compare with the observations. The modelled abundances are consistent with the observations, considering a late stage of the evolution of the prestellar core. However the calculated abundance of HNC3 was found 5-10 times higher than the observed one. The HC3N, HNC3 and HCCNC versus HC3NH+ ratios are compared in the TMC-1 dark cloud and the L1544 prestellar core., Comment: Accepted in MNRAS letters. 5 pages plus 2 additional pages for the on-line material
Published: 2017
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26. Vertical Structure of the Transition Zone from Infalling Rotating Envelope to Disk in the Class 0 Protostar, IRAS04368+2557

Author: Claudine Kahane, Aya E. Higuchi, Takeshi Sakai, Tomoyuki Hanawa, Nami Sakai, Emmanuel Caux, Charlotte Vastel, Tomoya Hirota, Cecilia Ceccarelli, Satoshi Yamamoto, Yoshimasa Watanabe, Yoko Oya, Ana López-Sepulcre, Bertrand Lefloch, Yuri Aikawa, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)
Subjects: Angular momentum, 010504 meteorology & atmospheric sciences, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, ISM: individual objects: L1527, 01 natural sciences, stars: low-mass, 0103 physical sciences, Transition zone, Protostar, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, ISM: kinematics and dynamics, Physics, stars: formation, Astronomy and Astrophysics, Rotational speed, Astrophysics - Astrophysics of Galaxies, Methods observational, ISM: molecules, [SDU]Sciences of the Universe [physics], Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), methods: observational
Abstract: International audience; We have resolved for the first time the radial and vertical structures of the almost edge-on envelope/disc system of the low-mass Class 0 protostar L1527. For that, we have used Atacama Large Millimetre/submillimetre Array (ALMA) observations with a spatial resolution of 0.25 × 0.13 arcsec2 and 0.37 × 0.23 arcsec2 at 0.8 and 1.2 mm, respectively. The L1527 dust continuum emission has a deconvolved size of 78 × 21 au2, and shows a flared disc-like structure. A thin infalling-rotating envelope is seen in the CCH emission outward of about 150 au, and its thickness is increased by a factor of 2 inward of it. This radius lies between the centrifugal radius (200 au) and the centrifugal barrier of the infalling-rotating envelope (100 au). The gas stagnates in front of the centrifugal barrier and moves towards vertical directions. SO emission is concentrated around and inside the centrifugal barrier. The rotation speed of the SO emitting gas is found to be decelerated around the centrifugal barrier. A part of the angular momentum could be extracted by the gas that moves away from the mid-plane around the centrifugal barrier. If this is the case, the centrifugal barrier would be related to the launching mechanism of low-velocity outflows, such as disc winds.
Published: 2017
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27. Complex organics in IRAS 4A revisited with ALMA and PdBI: Striking contrast between two neighbouring protostellar cores

Author: Emmanuel Caux, Nami Sakai, Charlotte Vastel, Roberto Neri, Muneaki Imai, Aya E. Higuchi, Claudine Kahane, Yuri Aikawa, Yoshimasa Watanabe, Satoshi Yamamoto, Bertrand Lefloch, Cecilia Ceccarelli, Yoko Oya, Tomoya Hirota, Ana López-Sepulcre, Sandrine Bottinelli, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Astrochemistry, stars: formation, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, astrochemistry, Plateau de Bure Interferometer, Binary number, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, 01 natural sciences, Astrophysics - Astrophysics of Galaxies, ISM: abundances, Wavelength, Interferometry, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Protostar, Millimeter, ISM: individual objects: NGC 1333 IRAS 4A, 010303 astronomy & astrophysics, Order of magnitude
Abstract: We used the Atacama Large (sub-)Millimeter Array (ALMA) and the IRAM Plateau de Bure Interferometer (PdBI) to image, with an angular resolution of 0.5$''$ (120 au) and 1$''$ (235 au), respectively, the emission from 11 different organic molecules in the protostellar binary NGC1333 IRAS 4A. We clearly disentangled A1 and A2, the two protostellar cores present. For the first time, we were able to derive the column densities and fractional abundances simultaneously for the two objects, allowing us to analyse the chemical differences between them. Molecular emission from organic molecules is concentrated exclusively in A2 even though A1 is the strongest continuum emitter. The protostellar core A2 displays typical hot corino abundances and its deconvolved size is 70 au. In contrast, the upper limits we placed on molecular abundances for A1 are extremely low, lying about one order of magnitude below prestellar values. The difference in the amount of organic molecules present in A1 and A2 ranges between one and two orders of magnitude. Our results suggest that the optical depth of dust emission at these wavelengths is unlikely to be sufficiently high to completely hide a hot corino in A1 similar in size to that in A2. Thus, the significant contrast in molecular richness found between the two sources is most probably real. We estimate that the size of a hypothetical hot corino in A1 should be less than 12 au. Our results favour a scenario in which the protostar in A2 is either more massive and/or subject to a higher accretion rate than A1, as a result of inhomogeneous fragmentation of the parental molecular clump. This naturally explains the smaller current envelope mass in A2 with respect to A1 along with its molecular richness., Comment: Accepted in Astronomy and Astrophysics
Published: 2017
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28. Detection of the HC$_3$NH$^+$ and HCNH$^+$ ions in the L1544 pre-stellar core

Author: Rafael Bachiller, P. Hily-Blant, Charlotte Vastel, Bertrand Lefloch, D. Quénard, Cecilia Ceccarelli, Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), and Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])
Subjects: Astrochemistry, molecular data, Thermodynamic equilibrium, Ionic bonding, FOS: Physical sciences, 01 natural sciences, Ion, TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY, 0103 physical sciences, Radiative transfer, Spectral resolution, 010303 astronomy & astrophysics, Hyperfine structure, Solar and Stellar Astrophysics (astro-ph.SR), Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, astrochemistry, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Pre-stellar core, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, radiative transfer, [SDU]Sciences of the Universe [physics], Astrophysics of Galaxies (astro-ph.GA), Atomic physics, line: identification
Abstract: The L1544 pre-stellar core was observed as part of the ASAI (Astrochemical Surveys At IRAM) Large Program. We report the first detection in a pre-stellar core of the HCNH$^+$ and HC$_3$NH$^+$ ions. The high spectral resolution of the observations allows to resolve the hyperfine structure of HCNH$^+$. Local thermodynamic equilibrium analysis leads to derive a column density equal to (2.0$\pm$0.2)$\times$10$^{13}$cm$^{-2}$ for HCNH$^+$ and (1.5$\pm$0.5)$\times$10$^{11}$cm$^{-2}$ for HC$_3$NH$^+$. We also present non-LTE analysis of five transitions of HC$_3$N, three transitions of H$^{13}$CN and one transition of HN$^{13}$C, all of them linked to the chemistry of HCNH$^+$ and HC$_3$NH$^+$. We computed for HC$_3$N, HCN, and HNC a column density of (2.0$\pm$0.4)$\times$10$^{13}$cm$^{-2}$, (3.6$\pm$0.9)$\times10^{14}$cm$^{-2}$, and (3.0$\pm$1.0)$\times$10$^{14}$cm$^{-2}$, respectively. We used the gas-grain chemical code Nautilus to predict the abundances all these species across the pre-stellar core. Comparison of the observations with the model predictions suggests that the emission from HCNH$^+$ and HC$_3$NH$^+$ originates in the external layer where non-thermal desorption of other species was previously observed. The observed abundance of both ionic species ([HCNH$^+$]$\,\simeq3\times10^{-10}$ and [HC$_3$NH$^+$]$\,\simeq[1.5-3.0]\times10^{-12}$, with respect to H$_2$) cannot be reproduced at the same time by the chemical modelling, within the error bars of the observations only. We discuss the possible reasons for the discrepancy and suggest that the current chemical models are not fully accurate or complete. However, the modelled abundances are within a factor of three consistent with the observations, considering a late stage of the evolution of the pre-stellar core, compatible with previous observations., Comment: Accepted for publication in MNRAS, 13 pages, 9 figures
Published: 2017
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29. Seeds Of Life In Space (SOLIS): The Organic Composition Diversity at 300-1000 au Scale in Solar-type Star-forming Regions

Author: R. Choudhury, Emmanuel Caux, Felipe O. Alves, Jacob C. Laas, Albert Rimola, François Dulieu, Satoshi Yamamoto, Charlotte Vastel, Francesco Fontani, Serena Viti, Anton Vasyunin, Leonardo Testi, E. Bianchi, Jonathan Holdship, Ana Chacón-Tanarro, Nami Sakai, P. Hily-Blant, J. Ospina, Sandrine Bottinelli, Claudine Kahane, Andy Pon, D. Quénard, Bertrand Lefloch, Piero Ugliengo, Laurent Wiesenfeld, Ana López-Sepulcre, R. Neri, Rafael Bachiller, Cecilia Ceccarelli, Jaime E. Pineda, Claudio Codella, Vianney Taquet, Cécile Favre, Paola Caselli, Anna Punanova, A. Jaber Al-Edhari, Patrice Theulé, Linda Podio, S. Spezzano, Luca Bizzocchi, Yoko Oya, Audrey Coutens, Siyi Feng, Nadia Balucani, Ian R. Sims, Izaskun Jiménez-Serra, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Max Planck Institute for Extraterrestrial Physics (MPE), Max-Planck-Gesellschaft, INAF - Osservatorio Astronomico di Brera (OAB), Istituto Nazionale di Astrofisica (INAF), INAF - Osservatorio Astrofisico di Arcetri (OAA), Queen Mary University of London (QMUL), University College of London [London] (UCL), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Perugia (UNIPG), Università degli Studi di Firenze [Firenze], Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), University of Western Ontario (UWO), Universitat Autònoma de Barcelona [Barcelona] (UAB), RIKEN - Institute of Physical and Chemical Research [Japon] (RIKEN), Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Università degli studi di Torino (UNITO), Ural Federal University [Ekaterinburg] (UrFU), Centre National de la Recherche Scientifique (CNRS), University of Electro-Communications [Tokyo] (UEC), European Research Council (ERC) [320620, 741002], French program Physique et Chimie du Milieu Interstellaire (PCMI) - Conseil National de la Recherche Scientifique (CNRS), Centre National dEtudes Spatiales (CNES), Italian Ministero dell'Istruzione, Universita e Ricerca, through the grant Progetti Premiali iALMA [CUP C52I13000140001], Canadian Institute for Theoretical Astrophysics (CITA) National Fellowship, STFC [ST/L004801, ST/M004139], Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Perugia = University of Perugia (UNIPG), Università degli Studi di Firenze = University of Florence (UniFI), LERMA Cergy (LERMA), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA (UMR_8112)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris-Seine-Université Paris-Seine-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Universitat Autònoma de Barcelona (UAB), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Università degli studi di Torino = University of Turin (UNITO), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Max-Planck-Institut fur Extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching, Germany, INAF-Osservatorio Astrofisico di Arcetri (INAF-OAA), Institut de RadioAstronomie Millimétrique (IRAM), Department of Physics and Astronomy, University College London, Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Université Fédérale Toulouse Midi-Pyrénées-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Observatorio Astronómico Nacional, Observatorio de Madrid, Alfonso XII (OAN), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Molécules dans l'Univers, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique et Atmosphères (LERMA (UMR_8112)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY), University of AL-Muthanna, College of Science, Physics Department, AL-Muthanna, Iraq, Department of Physics, University of Tokyo, Departament de Quimica, Universitat Autonoma de Barcelona, E-08193 Bellaterra, Spain, RIKEN The Institute of Physical and Chemical Research, Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Firenze = University of Florence [Firenze] (UNIFI), Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Cergy Pontoise (UCP), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)
Subjects: radio lines ISM, FOS: Physical sciences, Scale (descriptive set theory), Astrophysics, Type (model theory), Star (graph theory), Space (mathematics), ISM: clouds, 01 natural sciences, ISM: abundances, Spectral line, ISM molecules, Abundance (ecology), ISM: molecules, radio lines: ISM, Astronomy and Astrophysics, Space and Planetary Science, 0103 physical sciences, 14. Life underwater, 010303 astronomy & astrophysics, ISM abundances, Solar and Stellar Astrophysics (astro-ph.SR), ComputingMilieux_MISCELLANEOUS, Physics, [PHYS]Physics [physics], 010308 nuclear & particles physics, Astrophysics - Astrophysics of Galaxies, Interstellar medium, ISM clouds, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Astrophysics of Galaxies (astro-ph.GA), Molecular physics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Order of magnitude
Abstract: Complex organic molecules have been observed for decades in the interstellar medium. Some of them might be considered as small bricks of the macromolecules at the base of terrestrial life. It is hence particularly important to understand organic chemistry in Solar-like star forming regions. In this article, we present a new observational project: SOLIS (Seeds Of Life In Space). This is a Large Project at the IRAM-NOEMA interferometer, and its scope is to image the emission of several crucial organic molecules in a sample of Solar-like star forming regions in different evolutionary stage and environments. Here, we report the first SOLIS results, obtained from analysing the spectra of different regions of the Class 0 source NGC1333-IRAS4A, the protocluster OMC-2 FIR4, and the shock site L1157-B1. The different regions were identified based on the images of formamide (NH2CHO) and cyanodiacetylene (HC5N) lines. We discuss the observed large diversity in the molecular and organic content, both on large (3000-10000 au) and relatively small (300-1000 au) scales. Finally, we derive upper limits to the methoxy fractional abundance in the three observed regions of the same order of magnitude of that measured in few cold prestellar objects, namely ~10^-12-10^-11 with respect to H2 molecules., Comment: Accepted for publication on The Astrophysical Journal
Published: 2017
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30. L1157-B1, a factory of complex organic molecules in a Solar-type star forming region

Author: Charlotte Vastel, Rafael Bachiller, Cecilia Ceccarelli, Bertrand Lefloch, Cécile Favre, S. Viti, Linda Podio, Claudio Codella, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)
Subjects: Astrochemistry, Formic acid, Analytical chemistry, Ketene, FOS: Physical sciences, Astrophysics, 01 natural sciences, ISM: abundances, chemistry.chemical_compound, 0103 physical sciences, Dimethyl ether, 010303 astronomy & astrophysics, Physics, Glycolaldehyde, stars: formation, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], astrochemistry, 010308 nuclear & particles physics, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, ISM: molecules, Wavelength, ISM: jets and outflows, chemistry, [SDU]Sciences of the Universe [physics], Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Methanol, Excitation
Abstract: We report on a systematic search for oxygen-bearing Complex Organic Molecules (COMs) in the Solar-like protostellar shock region L1157-B1, as part of the IRAM Large Program "Astrochemical Surveys At IRAM" (ASAI). Several COMs are unambiguously detected, some for the first time, such as ketene H$_2$CCO, dimethyl ether (CH$_3$OCH$_3$) and glycolaldehyde (HCOCH$_2$OH), and others firmly confirmed, such as formic acid (HCOOH) and ethanol (C$_2$H$_5$OH). Thanks to the high sensitivity of the observations and full coverage of the 1, 2 and 3mm wavelength bands, we detected numerous (10--125) lines from each of the detected species. Based on a simple rotational diagram analysis, we derive the excitation conditions and the column densities of the detected COMs. Combining our new results with those previously obtained towards other protostellar objects, we found a good correlation between ethanol, methanol and glycolaldehyde. We discuss the implications of these results on the possible formation routes of ethanol and glycolaldehyde., Comment: 5 pages; 1 table; 3 figures; to appear in MNRAS
Published: 2017
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31. The onset of energetic particle irradiation in Class 0 protostars

Author: Marco Padovani, Asunción Fuente, Charlotte Vastel, Paola Caselli, Ana López-Sepulcre, Carsten Dominik, Bertrand Lefloch, Thierry Montmerle, Cecilia Ceccarelli, Dariusz C. Lis, J. Le Bourlot, Cecile Favre, Mihkel Kama, Emmanuel Caux, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), Univ Toulouse UPS, Ctr Etud Spatiale Rayonnements, F-31062 Toulouse 9, France, Centre Etud Spatiale Rayonnements Toulouse, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Institut de RadioAstronomie Millimétrique (IRAM), Centre National de la Recherche Scientifique (CNRS), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS Paris)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS-PSL), Low Energy Astrophysics (API, FNWI), and Faculty of Science
Subjects: Physics, [PHYS]Physics [physics], Range (particle radiation), 010504 meteorology & atmospheric sciences, Star formation, Star (game theory), FOS: Physical sciences, Order (ring theory), Flux, Astronomy and Astrophysics, Astrophysics, Astrophysics - Astrophysics of Galaxies, 01 natural sciences, Luminosity, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Ionization, 0103 physical sciences, Protostar, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: The early stages of low-mass star formation are likely to be subject to intense ionization by protostellar energetic MeV particles. As a result, the surrounding gas is enriched in molecular ions, such as HCO$^{+}$ and N$_{2}$H$^{+}$. Nonetheless, this phenomenon remains poorly understood for Class 0 objects. Recently, based on Herschel observations taken as part of the key program Chemical HErschel Surveys of Star forming regions (CHESS), a very low HCO$^{+}$/N$_{2}$H$^{+}$ abundance ratio of about 3-4, has been reported toward the protocluster OMC-2 FIR4. This finding suggests a cosmic-ray ionization rate in excess of 10$^{-14}$ s$^{-1}$, much higher than the canonical value of $\zeta$ = 3$\times$10$^{-17}$ s$^{-1}$ (value expected in quiescent dense clouds). To assess the specificity of OMC-2 FIR4, we have extended this study to a sample of sources in low- and intermediate mass. More specifically, we seek to measure the HCO$^{+}$/N$_2$H$^{+}$ abundance ratio from high energy lines (J $\ge$ 6) toward this source sample in order to infer the flux of energetic particles in the warm and dense gas surrounding the protostars. We use observations performed with the Heterodyne Instrument for the FarInfrared spectrometer on board the Herschel Space Observatory toward a sample of 9 protostars. We report HCO$^{+}$/N$_2$H$^{+}$ abundance ratios in the range of 5 up to 73 toward our source sample. The large error bars do not allow us to conclude whether OMC-2~FIR4 is a peculiar source. Nonetheless, an important result is that the measured HCO$^{+}$/N$_2$H$^{+}$ ratio does not vary with the source luminosity. At the present time, OMC-2 FIR4 remains the only source where a high flux of energetic particles is clearly evident. More sensitive and higher angular resolution observations are required to further investigate this process., Comment: Accepted for publication in A&A 18 pages, 12 figures, 15 tables
Published: 2017
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32. L483: Warm Carbon-Chain Chemistry Source Harboring Hot Corino Activity

Author: Charlotte Vastel, Nami Sakai, Yoshimasa Watanabe, Cecilia Ceccarelli, Yuri Aikawa, Satoshi Yamamoto, Takeshi Sakai, Bertrand Lefloch, Aya E. Higuchi, Emmanuel Caux, Tomoya Hirota, Yoko Oya, Ana López-Sepulcre, and Claudine Kahane
Subjects: Physics, SIMPLE (dark matter experiment), 010504 meteorology & atmospheric sciences, Resolution (electron density), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Radius, Astrophysics - Astrophysics of Galaxies, 01 natural sciences, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Molecule, Protostar, Chemical change, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), 0105 earth and related environmental sciences, Envelope (waves), Line (formation)
Abstract: The Class 0 protostar, L483, has been observed in various molecular lines in the 1.2 mm band at a sub-arcsecond resolution with ALMA. An infalling-rotating envelope is traced by the CS line, while a very compact component with a broad velocity width is observed for the CS, SO, HNCO, NH$_2$CHO, and HCOOCH$_3$ lines. Although this source is regarded as the warm carbon-chain chemistry (WCCC) candidate source at a 1000 au scale, complex organic molecules characteristic of hot corinos such as NH$_2$CHO and HCOOCH$_3$ are detected in the vicinity of the protostar. Thus, both hot corino chemistry and WCCC are seen in L483. Although such a mixed chemical character source has been recognized as an intermediate source in previous single-dish observations, we here report the first spatially-resolved detection. A kinematic structure of the infalling-rotating envelope is roughly explained by a simple ballistic model with the protostellar mass of 0.1--0.2 $M_\odot$ and the radius of the centrifugal barrier (a half of the centrifugal radius) of 30--200 au, assuming the inclination angle of 80\degr\ (0\degr\ for a face-on). The broad line emission observed in the above molecules most likely comes from the disk component inside the centrifugal barrier. Thus, a drastic chemical change is seen around the centrifugal barrier., Comment: accepted to ApJ
Published: 2017
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33. The Spatial Distribution of Complex Organic Molecules in the L1544 Pre-stellar Core

Author: Izaskun Jiménez-Serra, Charlotte Vastel, Leonardo Testi, Serena Viti, Bertrand Lefloch, Nicolas Billot, Rafael Bachiller, Anton Vasyunin, Paola Caselli, Nuria Marcelino, Institut national des sciences de l'Univers (France), Centre National de la Recherche Scientifique (France), Max Planck Society, Instituto Geográfico Nacional (España), European Commission, European Research Council, Ministero dell'Istruzione, dell'Università e della Ricerca, and Gothenburg Centre of Advanced Studies in Science and Technology
Subjects: Stars: formation, FOS: Physical sciences, Astrophysics, Spatial distribution, 01 natural sciences, Article, Organic molecules, 0103 physical sciences, ISM: Individual objects (L1544), 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), molecules [ISM], formation [Stars], Astrochemistry, Physics, Individual objects (L1544) [ISM], 010308 nuclear & particles physics, Radiation field, Astronomy and Astrophysics, Active surface, Astrophysics - Astrophysics of Galaxies, ISM: molecules, Pre-stellar core, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA)
Abstract: The detection of complex organic molecules (COMs) toward cold sources such as pre-stellar cores (with T=30 mag within the inner 2700 au; and a low-density shell with average Av~7.5-8 mag located at 4000 au from the core's center and bright in CH3OH. Our observations show that CH3O, CH3OCH3 and CH3CHO are more abundant (by factors ~2-10) toward the low-density shell than toward the continuum peak. Other COMs such as CH3OCHO, c-C3H2O, HCCCHO, CH2CHCN and HCCNC show slight enhancements (by factors, 16 pages, 3 figures, 2 tables. Accepted for publication in ApJ Letters
Published: 2016

34. Star Formation and Feedback: A Molecular Outflow-Prestellar Core Interaction in L1689N

Author: Laurent Pagani, Evelyne Roueff, C. M. Walmsley, Charlotte Vastel, F. F. S. van der Tak, Maryvonne Gerin, Dariusz C. Lis, H. A. Wootten, Astronomy, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Univ Toulouse UPS, Ctr Etud Spatiale Rayonnements, F-31062 Toulouse 9, France, Centre Etud Spatiale Rayonnements Toulouse, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS Paris)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), and PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)
Subjects: FOS: Physical sciences, Astrophysics, INITIAL CONDITIONS, 01 natural sciences, IRAS 16293-2422, 0103 physical sciences, Protostar, PHYSICAL CONDITIONS, GOULD BELT SURVEY, PRE-STELLAR CORE, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Physics, [PHYS]Physics [physics], HERSCHEL, stars: formation, INTERSTELLAR-MEDIUM, 010308 nuclear & particles physics, Star formation, TRIPLY DEUTERATED AMMONIA, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, ISM: molecules, Interstellar medium, Caltech Submillimeter Observatory, DEUTERIUM FRACTIONATION, 13. Climate action, Space and Planetary Science, techniques: interferometric, Astrophysics of Galaxies (astro-ph.GA), submillimeter: ISM, CLOUD CORES, Outflow, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], techniques: spectroscopic, Dust emission
Abstract: We present Herschel, ALMA Compact Array (ACA), and Caltech Submillimeter Observatory (CSO) observations of the prestellar core in L1689N, which has been suggested to be interacting with a molecular outflow driven by the nearby solar type protostar IRAS 16293-2422. This source is characterized by some of the highest deuteration levels seen in the interstellar medium. The change in the NH2D line velocity and width across the core provides clear evidence of an interaction with the outflow, traced by the high-velocity water emission. Quiescent, cold gas, characterized by narrow line widths is seen in the NE part of the core, while broader, more disturbed line profiles are seen in the W/SW part. Strong N2D+ and ND3 emission is detected with the ACA, extending S/SW from the peak of the single-dish NH2D emission. The ACA data also reveal the presence a compact dust continuum source, with a mean size of ~1100 au, a central density of (1-2) 10^7 cm-3, and a mass of 0.2-0.4 Msun. The dust emission peak is displaced ~5" to the south with respect to the N2D+ and ND3 emission, as well as the single-dish dust continuum peak, suggesting that the northern, quiescent part of the core is characterized by spatially extended continuum emission, which is resolved out by the interferometer. We see no clear evidence of fragmentation in this quiescent part of the core, which could lead to a second generation of star formation, although a weak dust continuum source is detected in this region in the ACA data., Accepted for publication in the Astrophysical Journal, 20 pages, 10 figures, 2 tables
Published: 2016
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35. Deuterium fractionation of a distant cold dark cloud along the line of sight of W51

Author: Bhaswati Mookerjea, Maryvonne Gerin, Jérôme Pety, Charlotte Vastel, Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), KOSMA, I. Physikalisches Institut, Universität zu Köln = University of Cologne, Institut de RadioAstronomie Millimétrique (IRAM), Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Univ Toulouse UPS, Ctr Etud Spatiale Rayonnements, F-31062 Toulouse 9, France, Centre Etud Spatiale Rayonnements Toulouse, Universität zu Köln, and École normale supérieure - Paris (ENS Paris)
Subjects: Astrochemistry, molecular data, FOS: Physical sciences, Astrophysics, 01 natural sciences, IRAM 30m telescope, law.invention, Telescope, law, 0103 physical sciences, Radiative transfer, Spectral resolution, Absorption (electromagnetic radiation), 010303 astronomy & astrophysics, Physics, Line-of-sight, 010308 nuclear & particles physics, astrochemistry, Molecular cloud, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, 13. Climate action, Space and Planetary Science, radiative transfer, Astrophysics of Galaxies (astro-ph.GA), [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], line: identification
Abstract: Herschel/HIFI observations toward the compact HII region W51 has revealed the presence of a cold dense core along its line of sight in a high-velocity stream located just in front of W51. This detection has been made possible through absorption measurements of low-energy transitions of HDO, NH3, and C3 against the bright background emitted by the star-forming region. We present a follow-up study of this core using the high sensitivity and high spectral resolution provided by the IRAM 30-meter telescope. We report new detections of this core in absorption for DCO+ (2-1, 3-2), H13CO+ (1-0), DNC (3-2), HN13C (1-0), p-H2CO (202-101, 303-202), and in emission for o-NH2D. We also report interferometric observation of this last species using the IRAM/NOEMA telescope, revealing the fragmented nature of the source through the detection of two cores, separated by 0.19 - 0.24 pc, with average sizes of less than 0.16 - 0.19 pc. From a non-LTE analysis, we are able to estimate the density (~2.5e4 cm-3) and temperature (~10 K) of this component, typical of what is found in dark clouds. This component (called W51-core) has the same DCO+/HCO+ ratio (0.02) as TMC-1 and a high DNC/HNC ratio (0.14). Detection of these deuterated species indicates that W51-core is similar to an early-phase low-mass star-forming region, formed from the interaction between the W51 giant molecular cloud and the high-velocity stream in front of it. The W51 complex being at about 5 kpc, these findings lead to what is the first detection of the earliest phase of low-mass star-forming region at such a large distance., Comment: 6 pages, 2 figures, accepted in Astronomy & Astrophysics
Published: 2016
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36. Detectability of deuterated water in prestellar cores

Author: Cecilia Ceccarelli, Charlotte Vastel, Paola Caselli, Vianney Taquet, D. Quénard, Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), and Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])
Subjects: Astrochemistry, Opacity, FOS: Physical sciences, Context (language use), Astrophysics, 7. Clean energy, 01 natural sciences, ISM: abundances, 0103 physical sciences, Radiative transfer, Protostar, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Line (formation), Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Star formation, astrochemistry, Astronomy and Astrophysics, Planetary system, ISM: molecules, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, ISM: individual objects: L1544, [SDU]Sciences of the Universe [physics], line: identification
Abstract: Water is an important molecule in the chemical and thermal balance of dense molecular gas, but knowing its history through-out the various stages of the star formation is a fundamental problem. Its molecular deuteration provides us with a crucial clue to its formation history. H$_2$O has recently been detected for the first time towards the prestellar core L1544 with the Herschel Space Observatory with a high spectral resolution (HIFI instrument). Prestellar cores provide the original reservoir of material from which future planetary systems are built, but few observational constraints exist on the formation of water and none on its deuteration before the collapse starts and a protostar forms at the centre. We report on new APEX observations of the ground state 1$_{0,1}$-0$_{0,0}$ HDO transition at 464 GHz towards the prestellar core L1544. The line is undetected, and we present an extensive study of the conditions for its detectability in cold and dense cloud cores. The water and deuterated water abundances have been estimated using an advanced chemical model simplified for the limited number of reactions or processes that are active in cold regions (< 15 K). We use the LIME radiative transfer code to compute the expected intensity and profile of both H$_2$O and HDO lines and compare them with the observations. We present several ad hoc profiles that best-fit the observations and compare the profiles with results from an astrochemical modelling, coupling gas phase and grain surface chemistry. Our comparison between observations, radiative transfer, and chemical modelling shows the limits of detectability for singly deuterated water, through the ground-state transitions 1$_{0,1}$-0$_{0,0}$ and 1$_{1,1}$-0$_{0,0}$ at 464.9 and 893.6 GHz, respectively, with both single-dish telescope and interferometric observations., 8 pages, 6 figures
Published: 2016
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37. Abundance of HOCO+ and CO2 in the outer layers of the L1544 prestellar core

Author: Bertrand Lefloch, Rafael Bachiller, Cecilia Ceccarelli, Charlotte Vastel, Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), and Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])
Subjects: Astrochemistry, molecular data, Abundance (chemistry), Analytical chemistry, FOS: Physical sciences, Protonation, Astrophysics, 01 natural sciences, Desorption, 0103 physical sciences, Radiative transfer, Molecule, 010303 astronomy & astrophysics, Line (formation), Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, astrochemistry, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Core (optical fiber), Space and Planetary Science, radiative transfer, [SDU]Sciences of the Universe [physics], Astrophysics of Galaxies (astro-ph.GA), line: identification
Abstract: The L1544 prestellar core has been observed as part of the ASAI IRAM Large Program at 3 mm. These observations led to the detection of many complex molecules. In this Letter, we report the detection of two lines, at 85.5 GHz (4,0,4-3,0,3) and 106.9 GHz (5,0,5-4,0,4), respectively, of the protonated carbon dioxide ion, HOCO+. We also report the tentative detection of the line at 100.4 GHz (5,0,5-4,0,4) of DOCO+. The non-LTE analysis of the detected lines shows that the HOCO+ emission originates in the external layer where non-thermal desorption of other species has previously been observed. Its abundance is (5 +/- 2) e-11. Modelling of the chemistry involved in the formation and destruction of HOCO+ provides a gaseous CO2 abundance of 2e-7 (with respect to H2) with an upper limit of 2e-6., Comment: To appear in A&A Letters
Published: 2016
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38. Phosphorus-bearing molecules in solar-type star-forming regions: first PO detection

Author: Serena Viti, Charlotte Vastel, Izaskun Jiménez-Serra, Rafael Bachiller, E. Mendoza, Bertrand Lefloch, Jacques Raymond Daniel Lépine, Cecilia Ceccarelli, Linda Podio, Claudio Codella, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, stars: formation, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010504 meteorology & atmospheric sciences, astrochemistry, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, 01 natural sciences, ISM: abundances, ISM: molecules, ISM: jets and outflows, [SDU]Sciences of the Universe [physics], Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, JATOS (ASTRONOMIA), 010303 astronomy & astrophysics, Humanities, 0105 earth and related environmental sciences
Abstract: As part of the Large Program ASAI (Astrochemical Surveys At IRAM), we have used the IRAM 30m telescope to lead a systematic search for the emission of rotational transitions of P-bearing species between 80 and 350 GHz towards L1157-B1, a shock position in the solar-type star forming region L1157. We report the detection of several transitions of PN and, for the first time, of prebiotic molecule PO. None of these species are detected towards the driving protostar of the outflow L1157-mm. Analysis of the line profiles shows that PN arises from the outflow cavity, where SiO, a strong shock tracer, is produced. Radiative transfer analysis yields an abundance of 2.5e-9 and 0.9e-9 for PO and PN, respectively. These results imply a strong depletion (approx 100) of Phosphorus in the quiescent cloud gas. Shock modelling shows that atomic N plays a major role in the chemistry of PO and PN. The relative abundance of PO and PN brings constraints both on the duration of the pre-shock phase, which has to be about 1 Myr, and on the shock parameters. The maximum temperature in the shock has to be larger than 4000K, which implies a shock velocity of 40 km/s., Comment: 9 pages, 4 figures
Published: 2016
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39. Structure of photodissociation fronts in star-forming regions revealed by Herschel observations of high-J CO emission lines

Author: Javier R. Goicoechea, Emilie Habart, Maryvonne Gerin, José Cernicharo, D. Teyssier, Carlos F. Pinto, Volker Ossenkopf-Okada, Christine Joblin, Olivier Berné, J. Montillaud, Charlotte Vastel, Emeric Bron, P. Pilleri, E. A. Bergin, Z. Nagy, M. Köhler, J. Le Bourlot, F. Le Petit, Markus Röllig, Asunción Fuente, Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Instituto de Física Fundamental [Madrid] (IFF), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Observatorio Astronómico Nacional (OAN), oan, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), European Space Astronomy Centre (ESAC), European Space Agency (ESA), Univers, Transport, Interfaces, Nanostructures, Atmosphère et environnement, Molécules (UMR 6213) (UTINAM), Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Univ Toulouse UPS, Ctr Etud Spatiale Rayonnements, F-31062 Toulouse 9, France, Centre Etud Spatiale Rayonnements Toulouse, Centro de Astrobiologia [Madrid] (CAB), Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Physikalisches Institut [Köln], Universität zu Köln, Department of Astronomy [Ann Arbor], University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS Paris)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), Consejo Superior de Investigaciones Científicas [Spain] (CSIC), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Franche-Comté (UFC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Ctr Astrobiol CSIC INTA, Lab Astrofis Mol, Madrid 28850, Spain, and Ctr Astrobiol CSIC INTA, Lab Astrofis Mol, Madrid
Subjects: Physics, 010308 nuclear & particles physics, Star formation, Molecular cloud, Photodissociation, Astronomy and Astrophysics, Context (language use), Astrophysics, 01 natural sciences, Photoevaporation, 13. Climate action, Space and Planetary Science, 0103 physical sciences, Emission spectrum, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Line (formation), Bar (unit)
Abstract: Context. In bright photodissociation regions (PDR) associated with massive star formation, the presence of dense “clumps” that are immersed in a less dense interclump medium is often proposed to explain the difficulty of models to account for the observed gas emission in high-excitation lines. Aims. We aim to present a comprehensive view of the modelling of the CO rotational ladder in PDRs, including the high-J lines that trace warm molecular gas at PDR interfaces. Methods. We observed the 12CO and 13CO ladders in two prototypical PDRs, the Orion Bar and NGC 7023 NW using the instruments onboard Herschel. We also considered line emission from key species in the gas cooling of PDRs (C+, O, and H2) and other tracers of PDR edges such as OH and CH+. All the intensities are collected from Herschel observations, the literature and the Spitzer archive and were analysed using the Meudon PDR code. Results. A grid of models was run to explore the parameter space of only two parameters: thermal gas pressure and a global scaling factor that corrects for approximations in the assumed geometry. We conclude that the emission in the high-J CO lines, which were observed up to Jup = 23 in the Orion Bar (Jup = 19 in NGC 7023), can only originate from small structures with typical thicknesses of a few 10−3 pc and at high thermal pressures (Pth ~ 108 K cm−3). Conclusions. Compiling data from the literature, we find that the gas thermal pressure increases with the intensity of the UV radiation field given by G0, following a trend in line with recent simulations of the photoevaporation of illuminated edges of molecular clouds. This relation can help to rationalise the analysis of high-J CO emission in massive star formation and provides an observational constraint for models which study stellar feedback on molecular clouds.
Published: 2018
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40. Survey of ortho-H$\mathsf{_{2}}$D$\mathsf{^{+}}$ (1$\mathsf{_{1,0}}$–1$\mathsf{_{1,1}}$) in dense cloud cores

Author: Antonio Crapsi, Charlotte Vastel, Paola Caselli, Cecilia Ceccarelli, Aurore Bacmann, and Floris van der Tak
Subjects: Physics, Chemical models, Astronomy and Astrophysics, Astrophysics, 01 natural sciences, Volume density, Caltech Submillimeter Observatory, Deuterium, 13. Climate action, Space and Planetary Science, Ionization, 0103 physical sciences, Ophiuchus, 010306 general physics, 010303 astronomy & astrophysics, Line (formation)
Abstract: We present a survey of the ortho-H2D+(1_{1,0}-1_{1,1}) line toward a sample of 10 starless cores and 6 protostellar cores, carried out at the Caltech Submillimeter Observatory. The high diagnostic power of this line is revealed for the study of the chemistry, and the evolutionary and dynamical status of low-mass dense cores. The line is detected in 7 starless cores and in 4 protostellar cores. N(ortho-H2D+) ranges between 2 and 40x10^{12} cm^{-2} in starless cores and between 2 and 9x10^{12} cm^{-2} in protostellar cores. The brightest lines are detected toward the densest and most centrally concentrated starless cores, where the CO depletion factor and the deuterium fractionation are also largest. The large scatter observed in plots of N(ortho-H2D+) vs. the observed deuterium fractionation and vs. the CO depletion factor is likely to be due to variations in the ortho-to-para (o/p) ratio of H2D+ from >0.5 for T_{kin} < 10 K gas in pre-stellar cores to ~0.03 (consistent with T_{kin} ~15 K for protostellar cores). The two Ophiuchus cores in our sample also require a relatively low o/p ratio (~0.3). Other parameters, including the cosmic-ray ionization rate, the CO depletion factor (or, more in general, the depletion factor of neutral species), the volume density, the fraction of dust grains and PAHs also largely affect the ortho-H2D+ abundance. The most deuterated and H2D+-rich objects (L429, L1544, L694-2 and L183) are reproduced by chemical models of centrally concentrated (central densties ~10^{6} cm^{-3}) cores with chemical ages between 10^4 and 10^6 yr. Upper limits of the para-H3O+ (1_1- -2_1+) and para-D2H+ (1_{1,0}-1_{0,1}) lines are also given. (Abridged)
Published: 2008
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41. Simultaneous Determination of the Cosmic Ray Ionization Rate and Fractional Ionization in DR 21(OH)

Author: Charlotte Vastel, Talayeh Hezareh, Martin Houde, Ruisheng Peng, and C. McCoey
Subjects: Physics, Abundance (chemistry), Molecular cloud, Astrophysics (astro-ph), FOS: Physical sciences, Astronomy and Astrophysics, Cosmic ray, Electron, Astrophysics, 01 natural sciences, Chemical reaction, 3. Good health, Space and Planetary Science, Ionization, 0103 physical sciences, Atomic physics, 010306 general physics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics
Abstract: We present a new method for the simultaneous calculation of the cosmic ray ionization rate, zeta(H2), and the ionization fraction, chi(e), in dense molecular clouds. A simple network of chemical reactions dominant in the creation and destruction of HCNH+ and HCO+ is used in conjunction with observed pairs of rotational transitions of several molecular species in order to determine the electron abundance and the H3+ abundance. The cosmic ray ionization rate is then calculated by taking advantage of the fact that, in dark clouds, it governs the rate of creation of H3+. We apply this technique to the case of the star-forming region DR21(OH), where we successfully detected the (J=3-2) and (J=4-3) rotational transitions of HCNH+. We also determine the C and O isotopic ratios in this source to be 12C/13C=63+-4 and 16O/18O=318+-64, which are in good agreement with previous measurements in other clouds. The significance of our method lies in the ability to determine N(H3+) and chi(e) directly from observations, and estimate zeta(H2) accordingly. Our results, zeta(H2)=3.1x10^(-18) 1/s and chi(e)=3.2x10^(-8), are consistent with recent determinations in other objects., Comment: 22 pages, including 3 figures
Published: 2008
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42. Deuterium enhancement in in pre-stellar cores

Author: Paola Caselli, Cecilia Ceccarelli, Laurent Pagani, Charlotte Vastel, and Thomas G. Phillips
Subjects: Physics, 010504 meteorology & atmospheric sciences, General Mathematics, Interstellar cloud, Polyatomic ion, Chemical fractionation, General Engineering, Analytical chemistry, General Physics and Astronomy, Zero-point energy, Astrophysics, 01 natural sciences, Deuterium, 13. Climate action, 0103 physical sciences, Molecule, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Line (formation)
Abstract: Deuterium enhancement of monodeuterated species has been recognized for more than 30 years as a result of chemical fractionation that results from the difference in zero-point energies of deuterated and hydrogenated molecules. The key reaction is the deuteron exchange in the reaction between HD, the reservoir of deuterium in dark interstellar clouds, and the molecular ion, leading to the production of H 2 D + molecule, and the low temperature in dark interstellar clouds favours this production. Furthermore, the presence of multiply deuterated species have incited our group to proceed further and consider the subsequent reaction of H 2 D + with HD, leading to D 2 H + , which can further react with HD to produce . In pre-stellar cores, where CO was found to be depleted, this production should be increased as CO would normally destroy . The first model including D 2 H + and predicted that these molecules should be as abundant as H 2 D + . The first detection of the D 2 H + was made possible by the recent laboratory measurement for the frequency of the fundamental line of para -D 2 H + . Here, we present observations of H 2 D + and D 2 H + towards a sample of dark clouds and pre-stellar cores and show how the distribution of ortho -H 2 D + (1 1,0 –1 1,1 ) can trace the deuterium factory in pre-stellar cores. We also present how future instrumentation will improve our knowledge concerning the deuterium enhancement of .
Published: 2006
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43. The Distribution of Ortho–H2D+(11,0–11,1) in L1544: Tracing the Deuteration Factory in Prestellar Cores

Author: Martin Houde, Charlotte Vastel, Cecilia Ceccarelli, Thomas G. Phillips, Paola Caselli, R. Peng, Martina C. Wiedner, Carsten Dominik, Laboratoire d'Astrophysique de Grenoble (LAOG), and Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Abundance (chemistry), Star formation, Astrophysics (astro-ph), Analytical chemistry, FOS: Physical sciences, Astronomy and Astrophysics, Fractionation, Radius, Astrophysics, 01 natural sciences, Distribution (mathematics), Deuterium, 13. Climate action, Space and Planetary Science, 0103 physical sciences, 010306 general physics, 010303 astronomy & astrophysics, Dust emission
Abstract: Prestellar cores are unique laboratories for studies of the chemical and physical conditions preceding star formation. We observed the prestellar core L1544 in the fundamental transition of ortho-H2D+ (1_1,0-1_1,1) at different positions over 100", and found a strong correlation between its abundance and the CO depletion factor. We also present a tentative detection of the fundamental transition of para-D2H+ (1_1,0-1_0,1) at the dust emission peak. Maps in N2H+, N2D+, HCO+ and DCO+ are used, and interpreted with the aid of a spherically symmetric chemical model that predicts the column densities and abundances of these species as a function of radius. The correlation between the observed deuterium fractionation of H3+, N2H+ and HCO+ and the observed integrated CO depletion factor across the core can be reproduced by this chemical model. In addition a simpler model is used to study the H2D+ ortho-to-para ratio. We conclude that, in order to reproduce the observed ortho-H2D+ observations, the grain radius should be larger than 0.3 microns., 24 pages, 9 figures, accepted in ApJ (to be published in July 2006)
Published: 2006
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44. Detection of D 2 H + in the Dense Interstellar Medium

Author: Charlotte Vastel, Hiroshige Yoshida, and Thomas G. Phillips
Subjects: Physics, Astrophysics (astro-ph), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, 01 natural sciences, Gas phase, Interstellar medium, Caltech Submillimeter Observatory, Deuterium, Space and Planetary Science, 0103 physical sciences, Protostar, 010306 general physics, 010303 astronomy & astrophysics, Line (formation)
Abstract: The 692 GHz para ground-state line of D2H+ has been detected at the Caltech Submillimeter Observatory towards the pre-stellar core 16293E. The derived D2H+ abundance is comparable to that of H2D+, as determined by observations of the 372 GHz line of ortho-H2D+. This is an observational verification of recent theoretical predictions (Roberts, Herbst & Millar 2003), developed to explain the large deuteration ratios observed in cold, high-density regions of the interstellar medium associated with low mass pre-stellar cores and protostars. This detection confirms expectations that the multiply deuterated forms of H3+ were missing factors of earlier models. The inclusion of D2H+ and D3+ in the models leads to predictions of higher values of the D/H ratio in the gas phase., 13 pages; accepted in ApJ Letters
Published: 2004
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45. First Detection of Doubly Deuterated Hydrogen Sulfide

Author: Charlotte Vastel, Thomas G. Phillips, John C. Pearson, and Cecilia Ceccarelli
Subjects: Physics, 010504 meteorology & atmospheric sciences, Hydrogen sulfide, Astrophysics (astro-ph), Formaldehyde, Analytical chemistry, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, 01 natural sciences, Isotopomers, Interstellar medium, chemistry.chemical_compound, Caltech Submillimeter Observatory, chemistry, Deuterium, 13. Climate action, Space and Planetary Science, 0103 physical sciences, Molecule, Methanol, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences
Abstract: This work was carried out with using the Caltech Submillimeter Observatory and presents the observational study of HDS and D2S towards a sample of Class 0 sources, and dense cores. We report the first detection of doubly deuterated hydrogen sulfide (D2S) in two dense cores and analyze the chemistry of these molecules aiming to help understand the deuteration processes in the interstellar medium. The observed values of the D2S/HDS ratio, and upper limits, require an atomic D/H ratio in the accreting gas of 0.1-1. The study presented in this Letter supports the hypothesis that formaldehyde, methanol and hydrogen sulfide are formed on the grain surfaces, during the cold pre-stellar core phase, where the CO depleted gas has large atomic D/H ratios. The high values for the D/H ratios are consistent with the predictions of a recent gas-phase chemical model that includes H3+ and its deuterated isotopomers, H2D+, D2H+ and D3+ (Roberts et al. 2003)., 14 pages, 2 figures. accepted in ApJL
Published: 2003
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46. Detection of a dense clump in a filament interacting with W51e2

Author: Charlotte Vastel, Carina M. Persson, Paul F. Goldsmith, Juergen Stutzki, Thomas F. Giesen, Maryvonne Gerin, John H. Black, Bhaswati Mookerjea, George E. Hassel, T. Harrison, Jérôme Pety, KOSMA, I. Physikalisches Institut, Universität zu Köln, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Institut de RadioAstronomie Millimétrique (IRAM), Centre National de la Recherche Scientifique (CNRS), Department of Materials Science and Engineering, KTH (KTH), Department of Materials Science and Engineering, KTH, Physikalisches Institut [Köln], Universität zu Köln = University of Cologne, Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), and École normale supérieure - Paris (ENS-PSL)
Subjects: Physics, [PHYS]Physics [physics], H II region, Astrochemistry, Line-of-sight, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics - Astrophysics of Galaxies, 01 natural sciences, Spectral line, Interstellar medium, Protein filament, Chemical species, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Protostar, 010306 general physics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS
Abstract: In the framework of the Herschel/PRISMAS Guaranteed Time Key Program, the line of sight to the distant ultracompact HII region W51e2 has been observed using several selected molecular species. Most of the detected absorption features are not associated with the background high-mass star-forming region and probe the diffuse matter along the line of sight. We present here the detection of an additional narrow absorption feature at ~70 km/s in the observed spectra of HDO, NH3 and C3. The 70 km/s feature is not uniquely identifiable with the dynamic components (the main cloud and the large-scale foreground filament) so-far identified toward this region. The narrow absorption feature is similar to the one found toward low-mass protostars, which is characteristic of the presence of a cold external envelope. The far-infrared spectroscopic data were combined with existing ground-based observations of 12CO, 13CO, CCH, CN, and C3H2 to characterize the 70 km/s component. Using a non-LTE analysis of multiple transitions of NH3 and CN, we estimated the density (n(H2) (1-5)x10^5 cm^-3) and temperature (10-30 K) for this narrow feature. We used a gas-grain warm-up based chemical model with physical parameters derived from the NH3 data to explain the observed abundances of the different chemical species. We propose that the 70 km/s narrow feature arises in a dense and cold clump that probably is undergoing collapse to form a low-mass protostar, formed on the trailing side of the high-velocity filament, which is thought to be interacting with the W51 main cloud. While the fortuitous coincidence of the dense clump along the line of sight with the continuum-bright W51e2 compact HII region has contributed to its non-detection in the continuum images, this same attribute makes it an appropriate source for absorption studies and in particular for ice studies of star-forming regions., Comment: Accepted for publication in A&A
Published: 2014
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47. Chemical modelling of water deuteration in IRAS16293-2422

Author: Emmanuel Caux, Sandrine Bottinelli, Audrey Coutens, Charlotte Vastel, Valentine Wakelam, Yuri Aikawa, Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire aquitain des sciences de l'univers (OASU), Université de Bordeaux (UB), AMOR 2014, Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB), CNRS INSU, UMR 5187, F-31028 Toulouse 4, France, UMR 5187 Toulouse, Univ Toulouse UPS, Ctr Etud Spatiale Rayonnements, F-31062 Toulouse 9, France, Centre Etud Spatiale Rayonnements Toulouse, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG ), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées
Subjects: Exothermic reaction, Astrochemistry, 010504 meteorology & atmospheric sciences, [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Evaporation, FOS: Physical sciences, Astrophysics, 7. Clean energy, 01 natural sciences, Chemical reaction, ISM: abundances, Ionization, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Protostar, ISM: IRAS16293-2422, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Envelope (waves), Physics, stars: protostars, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, ISM: molecules, Deuterium, 13. Climate action, Space and Planetary Science, Chemical physics, Astrophysics of Galaxies (astro-ph.GA), [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: IRAS 16293-2422 is a well studied low-mass protostar characterized by a strong level of deuterium fractionation. In the line of sight of the protostellar envelope, an additional absorption layer, rich in singly and doubly deuterated water has been discovered by a detailed multiline analysis of HDO. To model the chemistry in this source, the gas-grain chemical code Nautilus has been used with an extended deuterium network. For the protostellar envelope, we solve the chemical reaction network in infalling fluid parcels in a protostellar core model. For the foreground cloud, we explored several physical conditions (density, cosmic ionization rate, C/O ratio). The main results of the paper are that gas-phase abundances of H2O, HDO and D2O observed in the inner regions of IRAS16293-2422 are lower than those predicted by a 1D dynamical/chemical (hot corino) model in which the ices are fully evaporated. The abundance in the outer part of the envelope present chaotic profiles due to adsorption/evaporation competition, very different from the constant abundance assumed for the analysis of the observations. We also found that the large abundances of gas-phase H2O, HDO and D2O observed in the absorption layer are more likely explained by exothermic surface reactions rather than photodesorption processes., 20 pages, 15 figures. This version is slightly different from the published one because of language editor's modifications
Published: 2014
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48. Heavy water stratification in a low-mass protostar

Author: Charlotte Vastel, Vianney Taquet, Emmanuel Caux, Valentine Wakelam, Sandrine Bottinelli, Stéphanie Cazaux, Cecilia Ceccarelli, K. Demyk, Audrey Coutens, Astronomy, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG ), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), CNRS INSU, UMR 5187, F-31028 Toulouse 4, France, UMR 5187 Toulouse, AMOR 2013, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB), Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Univ Toulouse UPS, Ctr Etud Spatiale Rayonnements, F-31062 Toulouse 9, France, Centre Etud Spatiale Rayonnements Toulouse, Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), and Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB)
Subjects: 010504 meteorology & atmospheric sciences, FOS: Physical sciences, Astrophysics, DEUTERATED WATER, 7. Clean energy, 01 natural sciences, IRAS 16293-2422, MOLECULES, 0103 physical sciences, CO DEPLETION, EXCITATION, Radiative transfer, Protostar, Spectral resolution, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Physics, SPECTROSCOPY, INTERSTELLAR-MEDIUM, Star formation, astrochemistry, O(P-3)+H-2 REACTION, Molecular cloud, ICE, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Galaxy, ISM: individual objects: IRAS 16293-2422, ISM: molecules, Interstellar medium, DEUTERIUM FRACTIONATION, [PHYS.ASTR.GA]Physics [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], Low Mass
Abstract: Context: Despite the low elemental deuterium abundance in the Galaxy, enhanced molecular D/H ratios have been found in the environments of low-mass star-forming regions and, in particular, the Class 0 protostar IRAS 16293-2422. Aims: The key program Chemical HErschel Surveys of Star forming regions (CHESS) aims at studying the molecular complexity of the interstellar medium. The high sensitivity and spectral resolution of the Herschel/HIFI instrument provide a unique opportunity to observe the fundamental 1_{1,1}-0_{0,0} transition of ortho-D2O at 607 GHz and the higher energy 2_{1,2}-1_{0,1} transition of para-D2O at 898 GHz, both of which are inaccessible from the ground. Methods: The ortho-D2O transition at 607 GHz was previously detected. We present in this paper the first tentative detection for the para-D2O transition at 898 GHz. The spherical Monte Carlo radiative transfer code RATRAN was used to reproduce the observed line profiles of D2O with the same method that was used to reproduce the HDO and H2-18O line profiles in IRAS 16293-2422. Results: As for HDO, the absorption component seen on the D2O lines can only be reproduced by adding an external absorbing layer, possibly created by the photodesorption of the ices at the edges of the molecular cloud. The D2O column density is found to be about 2.5e12 cm^{-2} in this added layer, leading to a D2O/H2O ratio of about 0.5%. At a 3 sigma uncertainty, upper limits of 0.03% and 0.2% are obtained for this ratio in the hot corino and the colder envelope of IRAS 16293-2422, respectively. Conclusions: The deuterium fractionation derived in our study suggests that the ices present in IRAS 16293-2422 formed on warm dust grains (~15-20 K) in dense (~1e4-5e4 cm^{-3}) translucent clouds. These results allow us to address the earliest phases of star formation and the conditions in which ices form., Comment: 7 pages, 4 figures
Published: 2013
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49. Mono-deuterated dimethyl ether: laboratory spectrum up to 1 THz: torsion-rotational spectrum within the vibrational ground-state for the symmetric and asymmetric conformers and first detection in IRAS 16293-2422

Author: Cyril Richard, Emmanuel Caux, P. Groner, Laurent Margulès, Jean-Claude Guillemin, Charlotte Vastel, Claudine Kahane, Roman A. Motiyenko, Cecilia Ceccarelli, Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 (PhLAM), Université de Lille-Centre National de la Recherche Scientifique (CNRS), Univ Toulouse UPS, Ctr Etud Spatiale Rayonnements, F-31062 Toulouse 9, France, Centre Etud Spatiale Rayonnements Toulouse, CNRS INSU, UMR 5187, F-31028 Toulouse 4, France, UMR 5187 Toulouse, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG ), Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: molecular data, Terahertz radiation, Astrophysics, 010402 general chemistry, 01 natural sciences, Molecular physics, Radio spectrum, Isotopomers, law.invention, Telescope, methods: laboratory, chemistry.chemical_compound, Optics, law, 0103 physical sciences, Protostar, Dimethyl ether, 010303 astronomy & astrophysics, Physics, Spectrometer, business.industry, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Astronomy and Astrophysics, ISM: molecules, 0104 chemical sciences, chemistry, 13. Climate action, Space and Planetary Science, [SDU]Sciences of the Universe [physics], submillimeter: ISM, Ground state, business, techniques: spectroscopic, line: identification
Abstract: International audience; Context. Dimethyl ether is one of the most abundant complex organic molecules (COMs) in star-forming regions. Like other COMs, its formation process is not yet clearly established, but the relative abundances of its deuterated isotopomers may provide crucial hints in studying its chemistry and tracing the source history. The mono-deuterated species (CHDOCH) is still a relatively light molecule compared to other COMs. Its spectrum is the most intense in the THz domain in the 100-150 K temperature regime, tracing the inner parts of the low-mass star-forming region. Therefore, it is necessary to measure and assign its transitions in this range in order to be able to compute accurate predictions required by astronomical observations, in particular with the telescope operating in the submm range, such as ALMA. Aims. We present the analysis of mono-deuterated dimethyl ether in its ground-vibrational state, based on an effective Hamiltonian for an asymmetric rotor molecules with internal rotors. The analysis covers the frequency range 150-990 GHz. Methods. The laboratory rotational spectrum of this species was measured with a submillimeter spectrometer (50-990 GHz) using solid-state sources. For the astronomical detection, we used the IRAM 30 m telescope to observe a total range of 27 GHz, in 4 frequency bands from 100 GHz to 219 GHz. Results. New sets of spectroscopic parameters have been determined by a least squares fit with the ERHAM code for both conformers. These parameters have permitted the first identification in space of both mono-deuterated DME isomers via detection of twenty transitions in the solar-type protostar IRAS 16293-2422 with the IRAM 30 m telescope. The DME deuteration ratio in this source appears as high as observed for methanol and formaldehyde, two species known to play an important role in the COMs formation history.
Published: 2013
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50. Deuterated water in the solar-type protostars NGC 1333 IRAS 4A and IRAS 4B

Author: Adwin Boogert, Umut A. Yildiz, Berengere Parise, Charlotte Vastel, C. Comito, E. F. van Dishoeck, Audrey Coutens, Emmanuel Caux, Lars E. Kristensen, Fabrice Herpin, Claudio Codella, C. McCoey, F. F. S. van der Tak, S. Cabrit, Cecilia Ceccarelli, Bertrand Lefloch, Joseph C. Mottram, Ruud Visser, K. Demyk, Sandrine Bottinelli, Alain Castets, Vianney Taquet, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG ), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Univ Toulouse UPS, Ctr Etud Spatiale Rayonnements, F-31062 Toulouse 9, France, Centre Etud Spatiale Rayonnements Toulouse, CNRS INSU, UMR 5187, F-31028 Toulouse 4, France, UMR 5187 Toulouse, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Max-Planck-Institut für Extraterrestrische Physik (MPE), Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Max Planck Institute for Radio Astronomy, FORMATION STELLAIRE 2014, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB), foreign laboratories (FL), CERN [Genève], SRON Netherlands Institute for Space Research (SRON), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS-PSL), Universiteit Leiden, Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), and Astronomy
Subjects: 010504 meteorology & atmospheric sciences, FOS: Physical sciences, Astrophysics, Type (model theory), 01 natural sciences, ISM: abundances, 0103 physical sciences, Radiative transfer, Protostar, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Envelope (waves), Line (formation), Physics, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], astrochemistry, Astronomy and Astrophysics, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astrophysics - Astrophysics of Galaxies, ISM: molecules, Deuterium, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Outflow, ISM: individual objects: NGC 1333 IRAS 4A, ISM: individual objects: NGC 1333 IRAS 4B, Excitation, Galaxy Astrophysics
Abstract: Aims. The aim of this paper is to study deuterated water in the solar-type protostars NGC1333 IRAS4A and IRAS4B, to compare their HDO abundance distribution with other star-forming regions, and to constrain their HDO/H2O ratios. Methods. Using the Herschel/HIFI instrument as well as ground-based telescopes, we observed several HDO lines covering a large excitation range (Eup/k=22-168 K) towards these protostars and an outflow position. Non-LTE radiative transfer codes were then used to determine the HDO abundance profiles in these sources. Results. The HDO fundamental line profiles show a very broad component, tracing the molecular outflows, in addition to a narrower emission component and a narrow absorbing component. In the protostellar envelope of NGC1333 IRAS4A, the HDO inner (T>100 K) and outer (T, 16 pages, 13 figures
Published: 2013
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