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1. Exciton and Phonon Radiative Linewidths in Monolayer Boron Nitride

Author

G. Cassabois, G. Fugallo, C. Elias, P. Valvin, A. Rousseau, B. Gil, A. Summerfield, C. J. Mellor, T. S. Cheng, L. Eaves, C. T. Foxon, P. H. Beton, M. Lazzeri, A. Segura, S. V. Novikov, Laboratoire Charles Coulomb (L2C), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM), Laboratoire de Thermique et d’Energie de Nantes (LTeN), Centre National de la Recherche Scientifique (CNRS)-Nantes Université - Ecole Polytechnique de l'Université de Nantes (Nantes Univ - EPUN), Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ), School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Muséum national d'Histoire naturelle (MNHN)-Institut de recherche pour le développement [IRD] : UR206-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Departamento de Física Aplicada [Universitat Politècnica de València], Universitat Politècnica de València (UPV), ANR-19-CE08-0016,ZEOLIGHT,Prototype de LED UV à base de composite nitrure de bore/zéolithe pour la production de la lumière blanche(2019), and ANR-19-CE30-0007,BONASPES,Décrypter l'optique du h-BN en combinant des spectroscopies à haute résolution spatiale, énergétique et angulaire(2019)

Subjects
General Physics and Astronomy, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], ComputingMilieux_MISCELLANEOUS
Abstract

The light-matter interaction in bulk semiconductors is in the strong coupling regime with hybrid eigenstates, the so-called exciton-polaritons and phonon-polaritons. In two-dimensional (2D) systems, the translational invariance is broken in the direction perpendicular to the plane of the 2D system. The light-matter interaction switches to the weak coupling regime with a finite radiative lifetime of the matter excitations in 2D. Radiative phenomena have been extensively studied for 2D excitons in quantum wells and 2D crystals but their counterpart has never been addressed for optical phonons in 2D. Here we present a parallel study of the exciton and phonon radiative linewidths in atomically-thin layers of hexagonal boron nitride (hBN), epitaxially grown on graphite. Reflectivity experiments are performed either in the deep-ultraviolet for the excitonic resonance or in the mid-infrared for the phononic one. A quantitative interpretation is implemented in the framework of a transfer matrix approach generalized to the case of monolayers with the inclusion of BreitWigner resonances of either excitonic or phononic nature. For the exciton we find a giant radiative broadening in comparison to other 2D crystals, with a value of ?25 meV related to the strong excitonic effects in hBN. For the phonon we provide the first estimation of the radiative linewidth of a 2D phonon, with a value of ?0.2 meV in monolayer hBN. Our results are found to be in good agreement with first-principles calculations. Our study unravels the existence of radiative states for optical phonons in 2D, with numerous perspectives for fundamental physics, optoelectronic applications in the mid-infrared spectral range, and advanced thermal management, and hBN is emerging as a model system in this novel topic.

Published
2022
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4. The X-CLASS survey: A catalogue of 1646 X-ray-selected galaxy clusters up to z$\sim$1.5

Author

Koulouridis, E., Clerc, N., Sadibekova, T., Chira, M., Drigga, E., Faccioli, L., Fèvre, J.P. Le, Garrel, C., Gaynullina, E., Gkini, A., Kosiba, M., Pacaud, F., Pierre, M., Ridl, J., Tazhenova, K., Adami, C., Altieri, B., Baguley, J.-C., Cabanac, R., Cucchetti, E., Khalikova, A., Lieu, M., Melin, J.-B., Molham, M., Ramos-Ceja, M.E., Soucail, G., Takey, A., Valtchanov, I., Le Fèvre, J., Institut de recherche en astrophysique et planétologie (IRAP), 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), Institut de Recherche pour le Développement (IRD)-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)-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), 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 de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, 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), 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), Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing [Penteli] (IAASARS), National Observatory of Athens (NOA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Aristotle University of Thessaloniki, Ulugh Beg Astronomical Institute, Uzbekistan Academy of Sciences, Department of Astrophysics, Astronomy and Mechanics [Kapodistrian Univ], National and Kapodistrian University of Athens (NKUA), Masaryk University [Brno] (MUNI), Dipartimento di Fisica [Torino], Università degli studi di Torino (UNITO), Argelander Institute for Astronomy (AlfA), Rheinische Friedrich-Wilhelms-Universität Bonn, Max Planck Institute for Extraterrestrial Physics (MPE), Max-Planck-Gesellschaft, European Space Astronomy Centre (ESAC), European Space Agency (ESA), H. H. Wills Physics Laboratory [Bristol], University of Bristol [Bristol], School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), National Research Institute of Astronomy and Geophysics [Helwan] (NRIAG), Telespazio, Services par satellites, Operations Department (ESAC), European Space Agency (ESA)-European Space Agency (ESA), The Saclay team, Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), 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), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Università degli studi di Torino = University of Turin (UNITO), Agence Spatiale Européenne = European Space Agency (ESA), and Agence Spatiale Européenne = European Space Agency (ESA)-Agence Spatiale Européenne = European Space Agency (ESA)

Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO), media_common.quotation_subject, FOS: Physical sciences, Context (language use), Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, 0103 physical sciences, Cluster (physics), 010303 astronomy & astrophysics, Galaxy cluster, media_common, Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Redshift, Universe, Determining the number of clusters in a data set, Space and Planetary Science, Sky, Astrophysics of Galaxies (astro-ph.GA), Cluster sampling, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

Cosmological probes based on galaxy clusters rely on cluster number counts and large-scale structure information. X-ray cluster surveys are well suited for this purpose, since they are far less affected than optical surveys by projection effects, and cluster properties can be predicted with good accuracy. The XMM Cluster Archive Super Survey, X-CLASS, is a serendipitous search of X-ray-detected galaxy clusters in 4176 XMM-Newton archival observations until August 2015. All observations are clipped to exposure times of 10 and 20 ks to obtain uniformity and they span ~269 deg$^2$ across the high-Galactic latitude sky ($|b|> 20^o$). The main goal of the survey is the compilation of a well-selected cluster sample suitable for cosmological analyses. We describe the detection algorithm, the visual inspection, the verification process and the redshift validation of the cluster sample, as well as the cluster selection function computed by simulations. We also present the various metadata that are released with the catalogue, along with the redshifts of 124 clusters obtained with a dedicated multi-object spectroscopic follow-up programme. With this publication we release the new X-CLASS catalogue of 1646 well-selected X-ray-detected clusters over a wide sky area, along with their selection function. The sample spans a wide redshift range, from the local Universe up to z~1.5, with 982 spectroscopically confirmed clusters, and over 70 clusters above z=0.8. Because of its homogeneous selection and thorough verification, the cluster sample can be used for cosmological analyses, but also as a test-bed for the upcoming eROSITA observations and other current and future large-area cluster surveys. It is the first time that such a catalogue is made available to the community via an interactive database which gives access to a wealth of supplementary information, images, and data., Accepted for publication in A&A

Published
2021
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5. Direct band-gap crossover in epitaxial monolayer boron nitride

Author

Alex Summerfield, Guillaume Cassabois, Christopher J. Mellor, Peter H. Beton, Pierre Valvin, Bernard Gil, Laurence Eaves, Sergei V. Novikov, Tin S. Cheng, C. T. Foxon, Thomas Pelini, Christine Elias, Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Nanostructures quantiques propriétés optiques (NQPO), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Faculty of Engineering [Nottingham], University of Nottingham, UK (UON), School of Physics and Astronomy [Nottingham], and ANR-11-LABX-0014,GANEX,Réseau national sur GaN(2011)

Subjects
0301 basic medicine, Photoluminescence, Materials science, Science, General Physics and Astronomy, 02 engineering and technology, Two-dimensional materials, Epitaxy, Article, General Biochemistry, Genetics and Molecular Biology, law.invention, 03 medical and health sciences, chemistry.chemical_compound, law, Boron nitridewideband gap semiconductors2D Materialsvan der Waals epitaxy, Monolayer, Graphite, lcsh:Science, Nanoscale materials, Multidisciplinary, Graphene, business.industry, General Chemistry, 021001 nanoscience & nanotechnology, 030104 developmental biology, chemistry, Boron nitride, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Optoelectronics, Direct and indirect band gaps, lcsh:Q, 0210 nano-technology, business, Molecular beam epitaxy
Abstract

Hexagonal boron nitride is a large band-gap insulating material which complements the electronic and optical properties of graphene and the transition metal dichalcogenides. However, the intrinsic optical properties of monolayer boron nitride remain largely unexplored. In particular, the theoretically expected crossover to a direct-gap in the limit of the single monolayer is presently not confirmed experimentally. Here, in contrast to the technique of exfoliating few-layer 2D hexagonal boron nitride, we exploit the scalable approach of high-temperature molecular beam epitaxy to grow high-quality monolayer boron nitride on graphite substrates. We combine deep-ultraviolet photoluminescence and reflectance spectroscopy with atomic force microscopy to reveal the presence of a direct gap of energy 6.1 eV in the single atomic layers, thus confirming a crossover to direct gap in the monolayer limit., Insulating hexagonal boron nitride (hBN) is theoretically expected to undergo a crossover to a direct bandgap in the monolayer limit. Here, the authors perform optical spectroscopy measurements on atomically thin epitaxial hBN providing indications of the presence of a direct gap of energy 6.1 eV in the single atomic layer.

Published
2019
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9. Candidate fossil groups in the CFHTLS: a probabilistic approach

Author

C. Adami, Florian Sarron, Florence Durret, Nicolas Martinet, 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), School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Institut d'Astrophysique de Paris (IAP), and Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO), Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Context (language use), Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Luminosity, galaxies: groups: general, Galaxy group, 0103 physical sciences, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, COSMIC cancer database, Mass distribution, 010308 nuclear & particles physics, Group (mathematics), Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Galaxy, Redshift, Space and Planetary Science, galaxies: clusters: general, Astrophysics of Galaxies (astro-ph.GA), X-rays: galaxies: clusters, large-scale structure of Universe, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

Fossil groups (FGs) have been discovered twenty-five years ago, and are now defined as galaxy groups with an X-ray luminosity higher than $10^{42}\ h_{50}^{-2}$ erg s$^{-1}$ and a brightest group galaxy brighter than the other group members by at least 2 magnitudes. However, the scenario of their formation remains controversial. We propose here a probabilistic analysis of FGs, extracted from the large catalogue of candidate groups and clusters detected by Sarron et al. (2018) in the CFHTLS survey, based on photometric redshifts, to investigate their position in the cosmic web and probe their environment. Based on spectroscopic and photometric redshifts, we estimate the probability of galaxies to belong to a galaxy structure, and by imposing the condition that the brightest group galaxy is at least brighter than the others by 2 magnitudes, we compute the probability for a given galaxy structure to be a FG. We analyse the mass distribution of these candidate FGs, and estimate their distance to the filaments and nodes of the cosmic web in which they are embedded. We find that the structures with masses lower than $2.4\times 10^{14}$ M$_\odot$ have the highest probabilities of being fossil groups (PFG). Overall, structures with PFG$\geq$50% are located close to the cosmic web filaments (87% are located at less than 1 Mpc from their nearest filament). They are preferentially four times more distant from their nearest node than from their nearest filament. We confirm that FGs have small masses and are rare. They seem to reside closeby cosmic filaments and do not survive in nodes. Being in a poor environment could therefore be the driver of FG formation, the number of nearby galaxies not being sufficient to compensate for the cannibalism of the central group galaxy., Comment: 9 pages, 4 figures, A&A accepted, A&A improved english

Published
2020
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10. Spitzer Catalog of Herschel-selected ultrared dusty star-forming galaxies

Author

Dominik A. Riechers, Elisabete da Cunha, Steve Maddox, Alain Omont, Ismael Perez-Fournon, Arianna Brown, Rob Ivison, J. Greenslade, Stephen Anthony Eales, Seb Oliver, Simon Dye, Julie Wardlow, Elisabetta Valiante, Douglas Scott, Asantha Cooray, Andrew Battisti, Jingzhe Ma, Stephen Serjeant, Loretta Dunne, David L. Clements, Pierre Cox, Mattia Negrello, N. Ghotbi, Hooshang Nayyeri, S. Duivenvoorden, Matthew L. N. Ashby, Ivan Oteo, Department of Physics and Astronomy [Irvine], University of California [Irvine] (UCI), University of California-University of California, Royal Observatory Edinburgh (ROE), University of Edinburgh, Astronomy Centre, University of Sussex, Department of Astronomy, University of Massachusetts [Amherst] (UMass Amherst), University of Massachusetts System (UMASS), Cornell University [New York], School of Physics and Astronomy [Cardiff], Cardiff University, Institut d'Astrophysique de Paris (IAP), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Department of Physics and Astronomy [Vancouver], University of British Columbia (UBC), School of Physics and Astronomy [Nottingham], and University of Nottingham, UK (UON)

Subjects
Stellar mass, DEEP FIELD, INFRARED-EMISSION, Population, Extinction (astronomy), FOS: Physical sciences, Astrophysics, Astronomy & Astrophysics, 01 natural sciences, LYMAN BREAK GALAXIES, Luminosity, EXTRAGALACTIC SURVEY, BOLOMETER CAMERA, 0103 physical sciences, 0201 Astronomical and Space Sciences, SIMPLE-MODEL, education, NUMBER COUNTS, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Physics, 0306 Physical Chemistry (incl. Structural), education.field_of_study, Science & Technology, SUBMILLIMETER GALAXIES, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Star formation, Astronomy and Astrophysics, MASSIVE GALAXIES, Astrophysics - Astrophysics of Galaxies, Redshift, Galaxy, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics of Galaxies (astro-ph.GA), Physical Sciences, 0202 Atomic, Molecular, Nuclear, Particle and Plasma Physics, REDSHIFT DISTRIBUTION, Spectral energy distribution
Abstract

The largest Herschel extragalactic surveys, H-ATLAS and HerMES, have selected a sample of "ultrared" dusty, star-forming galaxies (DSFGs) with rising SPIRE flux densities ($S_{500} > S_{350} > S_{250}$; so-called "500 $��$m-risers") as an efficient way for identifying DSFGs at higher redshift ($z > 4$). In this paper, we present a large Spitzer follow-up program of 300 Herschel ultrared DSFGs. We have obtained high-resolution ALMA, NOEMA, and SMA data for 63 of them, which allow us to securely identify the Spitzer/IRAC counterparts and classify them as gravitationally lensed or unlensed. Within the 63 ultrared sources with high-resolution data, $\sim$65% appear to be unlensed, and $\sim$27% are resolved into multiple components. We focus on analyzing the unlensed sample by directly performing multi-wavelength spectral energy distribution (SED) modeling to derive their physical properties and compare with the more numerous $z \sim 2$ DSFG population. The ultrared sample has a median redshift of 3.3, stellar mass of 3.7 $\times$ 10$^{11}$ $M_{\odot}$, star formation rate (SFR) of 730 $M_{\odot}$yr$^{-1}$, total dust luminosity of 9.0 $\times$ 10$^{12}$ $L_{\odot}$, dust mass of 2.8 $\times$ 10$^9$ $M_{\odot}$, and V-band extinction of 4.0, which are all higher than those of the ALESS DSFGs. Based on the space density, SFR density, and stellar mass density estimates, we conclude that our ultrared sample cannot account for the majority of the star-forming progenitors of the massive, quiescent galaxies found in infrared surveys. Our sample contains the rarer, intrinsically most dusty, luminous and massive galaxies in the early universe that will help us understand the physical drivers of extreme star formation., 33 pages, 10 figures; accepted for publication in ApJS. The catalog tables will be available on ApJS and VizieR; authors' version is available now upon request

Published
2019
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11. High-Frequency Elastic Coupling at the Interface of van der Waals Nanolayers Imaged by Picosecond Ultrasonics

Author

Jake D. G. Greener, A. V. Akimov, Amalia Patanè, Anthony J. Kent, Elton de Lima Savi, Zakhar R. Kudrynskyi, Nikolay Chigarev, Vitalyi Gusev, Zakhar D. Kovalyuk, Samuel Raetz, School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Laboratoire d'Acoustique de l'Université du Mans (LAUM), Centre National de la Recherche Scientifique (CNRS)-Le Mans Université (UM), and National Academy of Sciences of Ukraine (NASU)

Subjects
Materials science, General Physics and Astronomy, 02 engineering and technology, Substrate (electronics), 010402 general chemistry, phonon imaging, 01 natural sciences, law.invention, symbols.namesake, Scanning probe microscopy, picosecond ultrasonics, law, General Materials Science, elastic interface coupling, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, Coupling, Range (particle radiation), business.industry, Graphene, General Engineering, Heterojunction, 021001 nanoscience & nanotechnology, 0104 chemical sciences, [PHYS.MECA.ACOU]Physics [physics]/Mechanics [physics]/Acoustics [physics.class-ph], coherent phonons, symbols, Picosecond ultrasonics, Optoelectronics, van der Waals nanolayers, pump−probe technique, van der Waals force, 0210 nano-technology, business
Abstract

International audience; Although the topography of van de Waals (vdW) layers and heterostructures can be imaged by scanning probe microscopy, high-frequency interface elastic properties are more difficult to assess. These can influence the stability, reliability, and performance of electronic devices that require uniform layers and interfaces. Here, we use picosecond ultrasonics to image these properties in vdW layers and heterostructures based on well-known exfoliable materials, i.e., InSe, hBN, and graphene. We reveal a strong, uniform elastic coupling between vdW layers over a wide range of frequencies of up to tens of gigahertz (GHz) and in-plane areas of 100 μm2. In contrast, the vdW layers can be weakly coupled to their supporting substrate, behaving effectively as free-standing membranes. Our data and analysis demonstrate that picosecond ultrasonics offers opportunities to probe the high-frequency elastic coupling of vdW nanolayers and image both “perfect” and “broken” interfaces between different materials over a wide frequency range, as required for future scientific and technological developments.

Published
2019
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12. Astro2020 Science White Paper: Primordial Non-Gaussianity

Author

Meerburg, P. Daniel, Green, Daniel, Abidi, Muntazir, Amin, Mustafa A., Adshead, Peter, Ahmed, Zeeshan, Alonso, David, Ansarinejad, Behzad, Armstrong, Robert, Ávila, Santiago, Baccigalupi, Carlo, Baldauf, Tobias, Ballardini, Mario, Bandura, Kevin, Bartolo, Nicola, Battaglia, Nicholas, Baumann, Daniel, Bavdhankar, Chetan, Bernal, José Luis, Beutler, Florian, Biagetti, Matteo, Bischoff, Colin, Blazek, Jonathan, Bond, J. Richard, Borrill, Julian, Bouchet, François R., Bull, Philip, Burgess, Cliff, Byrnes, Christian, Calabrese, Erminia, Carlstrom, John E., Castorina, Emanuele, Challinor, Anthony, Chang, Tzu-Ching, Chaves-Montero, Jonas, Chen, Xingang, Yeche, Christophe, Cooray, Asantha, Coulton, William, Crawford, Thomas, Chisari, Elisa, Cyr-Racine, Francis-Yan, d'Amico, Guido, de Bernardis, Paolo, de La Macorra, Axel, Dore, Olivier, Duivenvoorden, Adri, Dunkley, Joanna, Dvorkin, Cora, Eggemeier, Alexander, Escoffier, Stephanie, Essinger-Hileman, Tom, Fasiello, Matteo, Ferraro, Simone, Flauger, Raphael, Font-Ribera, Andreu, Foreman, Simon, Friedrich, Oliver, Garcia-Bellido, Juan, Gerbino, Martina, Gluscevic, Vera, Goon, Garrett, Gorski, Krzysztof M., Gudmundsson, Jon E., Gupta, Nikhel, Hanany, Shaul, Handley, Will, Hawken, Adam J., Hill, J. Colin, Hirata, Christopher M., Hložek, Renée, Holder, Gilbert, Huterer, Dragan, Kamionkowski, Marc, Karkare, Kirit S., Keeley, Ryan E., Kinney, William, Kisner, Theodore, Kneib, Jean-Paul, Knox, Lloyd, Koushiappas, Savvas M., Kovetz, Ely D., Koyama, Kazuya, L'Huillier, Benjamin, Lahav, Ofer, Lattanzi, Massimiliano, Lee, Hayden, Liguori, Michele, Loverde, Marilena, Madhavacheril, Mathew, Maldacena, Juan, Marsh, M. C. David, Masui, Kiyoshi, Matarrese, Sabino, Mcallister, Liam, Mcmahon, Jeff, Mcquinn, Matthew, Meyers, Joel, Mirbabayi, Mehrdad, Dizgah, Azadeh Moradinezhad, Motloch, Pavel, Mukherjee, Suvodip, Muñoz, Julian B., Myers, Adam D., Nagy, Johanna, Naselsky, Pavel, Nati, Federico, Nicolis, Alberto, Niemack, Michael D., Niz, Gustavo, Nomerotski, Andrei, Page, Lyman, Pajer, Enrico, Padmanabhan, Hamsa, Palma, Gonzalo A., Peiris, Hiranya V., Percival, Will J., Piacentni, Francesco, Pimentel, Guilherme L., Pogosian, Levon, Prescod-Weinstein, Chanda, Pryke, Clement, Puglisi, Giuseppe, Racine, Benjamin, Stompor, Radek, Raveri, Marco, Remazeilles, Mathieu, Rocha, Gracca, Ross, Ashley J., Rossi, Graziano, Ruhl, John, Sasaki, Misao, Schaan, Emmanuel, Schillaci, Alessandro, Schmittfull, Marcel, Sehgal, Neelima, Senatore, Leonardo, Seo, Hee-Jong, Shan, Huanyuan, Shandera, Sarah, Sherwin, Blake D., Silverstein, Eva, Simon, Sara, Slosar, Anže, Staggs, Suzanne, Starkman, Glenn, Stebbins, Albert, Suzuki, Aritoki, Switzer, Eric R., Timbie, Peter, Tolley, Andrew J., Tomasi, Maurizio, Tristram, Matthieu, Trodden, Mark, Tsai, Yu-Dai, Uhlemann, Cora, Umiltà, Caterina, van Engelen, Alexander, Vargas-Magaña, M., Vieregg, Abigail, Wallisch, Benjamin, Wands, David, Wandelt, Benjamin, Wang, Yi, Watson, Scott, Wise, Mark, Wu, W. L. K., Xianyu, Zhong-Zhi, Xu, Weishuang, Yasini, Siavash, Young, Sam, Yutong, Duan, Zaldarriaga, Matias, Zemcov, Michael, Zhao, Gong-Bo, Zheng, Yi, Zhu, Ningfeng, University of Cambridge [UK] (CAM), University of California [San Diego] (UC San Diego), University of California (UC), Universidad Autónoma de Madrid (UAM), Institute of Cosmology and Gravitation [Portsmouth] (ICG), University of Portsmouth, Ecole Polytechnique Fédérale de Lausanne (EPFL), Canadian Institute for Theoretical Astrophysics (CITA), Lawrence Berkeley National Laboratory [Berkeley] (LBNL), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Argonne National Laboratory [Lemont] (ANL), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Kavli Institute for Particle Astrophysics and Cosmology (KIPAC), Stanford University, Facultad de Ingeniería [Buenos Aires] (FIUBA), Universidad de Buenos Aires [Buenos Aires] (UBA), Dipartimento di Fisica [Roma La Sapienza], Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM), Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), University College of London [London] (UCL), National Oceanography Centre [Southampton] (NOC), University of Southampton, Johns Hopkins University (JHU), Korea Astronomy and Space Science Institute (KASI), ICRA and Physics Department, Columbia University [New York], Dipartimento di Fisica 'G. Galilei', Università degli Studi di Padova = University of Padua (Unipd), Kavli Institute for Cosmological Physics [Chicago] (KICP), University of Chicago, School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Institute for Astronomy [Zürich], Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), University of Waterloo [Waterloo], University of New Hampshire (UNH), Istituto Nazionale di Geofisica e Vulcanologia - Sezione di Catania (INGV), Istituto Nazionale di Geofisica e Vulcanologia, Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, APC - Cosmologie, AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), University of Manchester [Manchester], Brookhaven National Laboratory [Upton, NY] (BNL), UT-Battelle, LLC-Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY)-U.S. Department of Energy [Washington] (DOE), Laboratoire de l'Accélérateur Linéaire (LAL), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre for Theoretical Cosmology, Institute for Advanced Study Princeton, School of physics and astronomy, Rochester Institute of Technology, University of California, Universidad Autonoma de Madrid (UAM), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Universidad Nacional Autónoma de México (UNAM), Okayama University, Universita degli Studi di Padova, Smithsonian Institution-Harvard University [Cambridge], Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), U.S. Department of Energy [Washington] (DOE)-UT-Battelle, LLC-Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), and Universidad Nacional Autónoma de México - UNAM (MEXICO)

Subjects
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics::Cosmology and Extragalactic Astrophysics
Abstract

5 pages + references; Submitted to the Astro2020 call for science white papers. This version: fixed author list; International audience; Our current understanding of the Universe is established through the pristine measurements of structure in the cosmic microwave background (CMB) and the distribution and shapes of galaxies tracing the large scale structure (LSS) of the Universe. One key ingredient that underlies cosmological observables is that the field that sources the observed structure is assumed to be initially Gaussian with high precision. Nevertheless, a minimal deviation from Gaussianityis perhaps the most robust theoretical prediction of models that explain the observed Universe; itis necessarily present even in the simplest scenarios. In addition, most inflationary models produce far higher levels of non-Gaussianity. Since non-Gaussianity directly probes the dynamics in the early Universe, a detection would present a monumental discovery in cosmology, providing clues about physics at energy scales as high as the GUT scale.

Published
2019

13. Imaging human cortical responses to intraneural microstimulation using magnetoencephalography

Author

Paul Glover, George C. O'Neill, Rosa Maria Sanchez Panchuelo, Ayan Sengupta, Michael Asghar, Rochelle Ackerley, Eleanor L. Barratt, Susan T. Francis, Roger Holmes Watkins, Matthew J. Brookes, Johan Wessberg, School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Department of Physiology, University of Gothenburg (GU), Göteborgs Universitet (GU), Neurosciences sensorielles et cognitives (NSC), and Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Adult, Male, Central nervous system, Single-unit, Stimulation, Biology, Somatosensory system, Vibration, Article, Young Adult, 03 medical and health sciences, 0302 clinical medicine, Rhythm, Cortex (anatomy), Sensation, medicine, Humans, Microstimulation, Aged, 030304 developmental biology, Afferent Pathways, 0303 health sciences, medicine.diagnostic_test, [SCCO.NEUR]Cognitive science/Neuroscience, Magnetoencephalography, Somatosensory Cortex, Middle Aged, Hand, Electric Stimulation, medicine.anatomical_structure, Touch Perception, Intraneural microstimulation, Female, Beta Rhythm, Mechanoreceptors, Neuroscience, 030217 neurology & neurosurgery
Abstract

The sensation of touch in the glabrous skin of the human hand is conveyed by thousands of fast-conducting mechanoreceptive afferents, which can be categorised into four distinct types. The spiking properties of these afferents in the periphery in response to varied tactile stimuli are well-characterised, but relatively little is known about the spatiotemporal properties of the neural representations of these different receptor types in the human cortex. Here, we use the novel methodological combination of single-unit intraneural microstimulation (INMS) with magnetoencephalography (MEG) to localise cortical representations of individual touch afferents in humans, by measuring the extracranial magnetic fields from neural currents. We found that by assessing the modulation of the beta (13–30 Hz) rhythm during single-unit INMS, significant changes in oscillatory amplitude occur in the contralateral primary somatosensory cortex within and across a group of fast adapting type I mechanoreceptive afferents, which corresponded well to the induced response from matched vibrotactile stimulation. Combining the spatiotemporal specificity of MEG with the selective single-unit stimulation of INMS enables the interrogation of the central representations of different aspects of tactile afferent signalling within the human cortices. The fundamental finding that single-unit INMS ERD responses are robust and consistent with natural somatosensory stimuli will permit us to more dynamically probe the central nervous system responses in humans, to address questions about the processing of touch from the different classes of mechanoreceptive afferents and the effects of varying the stimulus frequency and patterning., Highlights • We combine MEG with single unit INMS to image cortical responses to stimulation of the fundaments of touch. • Stimulating individual fast adapting type I mechanoreceptors in the hand shows changes in beta oscillatory power in S1. • Comparing results to vibrotactile stimulation experiments show the results to be as robust as conventional stimuli. • Imaging responses to INMS could allow us to test emerging theories about beta burst events.

Published
2019
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14. Dressed dense atomic gases

Author

Igor Lesanovsky, Beatriz Olmos, William Guerin, Robin Kaiser, School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), and Université Côte d'Azur (UCA)

Subjects
Physics, Quantum Physics, Photon, [PHYS.PHYS.PHYS-ATOM-PH]Physics [physics]/Physics [physics]/Atomic Physics [physics.atom-ph], Field (physics), Atomic Physics (physics.atom-ph), FOS: Physical sciences, Dissipation, Laser, 01 natural sciences, Physics - Atomic Physics, 010305 fluids & plasmas, law.invention, Dipole, law, Excited state, 0103 physical sciences, Quasiparticle, Rotational spectroscopy, Atomic physics, 010306 general physics, Quantum Physics (quant-ph), ComputingMilieux_MISCELLANEOUS
Abstract

In dense atomic gases the interaction between transition dipoles and photons leads to the formation of many-body states with collective dissipation and long-ranged forces. Despite decades of research, a full understanding of this paradigmatic many-body problem is still lacking. Here, we put forward and explore a scenario in which a dense atomic gas is weakly excited by an off-resonant laser field. We develop the theory for describing such dressed many-body ensembles and show that collective excitations are responsible for the emergence of many-body interactions, i.e. effective potentials that cannot be represented as a sum of binary terms. We illustrate how interaction effects may be probed through microwave spectroscopy via the analysis of time-dependent line-shifts, and show that these signals are sensitive to the phase pattern of the dressing laser. Our study offers a new perspective on dense atomic ensembles interacting with light and promotes this platform as a setting for the exploration of rich non-equilibrium many-body physics.

Published
2019
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15. MEG compatible microneurography and intra-neural microstimulation instrumentation

Author

O'Neill, George, Wessberg, Johan, Watkins, Roger, Ackerley, Rochelle, Glover, Paul, Witton, Caroline, Furlong, Paul, Hall, Michael, Brookes, Matthew, Francis, Susan, School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Göteborgs Universitet (GU), Neurosciences sensorielles et cognitives (NSC), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Aston University [Birmingham], Ackerley, Rochelle, and Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SCCO.NEUR]Cognitive science/Neuroscience, [SCCO.NEUR] Cognitive science/Neuroscience
Abstract

International audience; Background Microneurography is an established technique whereby a tungsten electrode is placed within a human peripheral nerve bundle, where single afferents can be distinguished. The electrode can be used to record the activity of a single unit, or by applying a short train of pulses at microampere levels, a localised sensation can be perceived, which has qualities that match the physiologically-defined unit. Single unit intra-neural microstimulation provides an extremely specific input to the brain, thought to be at the quantal level. Microneurography has been used for functional MRI, but it has not been tested in MEG, which provides excellent temporal resolution. Commercial systems have limitations due to: magnetic components (relays or other ferrites); potentially hazardous long cables; or long recovery when switching between recording and stimulating modes. Methods The key to the success of designing an instrument capable of fulfilling the requirements was using opto-coupled FET analogue switches to route connections from the electrodes to either the recording amplifier or the current stimulator. The amplifier comprised a low-noise instrumentation amplifier with a bandwidth of 1–10 kHz. The signals were digitised, filtered, recorded, and passed to an audio feed so that the microneurographer could hear the nerve signals whilst positioning the electrode. The instrumentation was opto-isolated for safe operation. A stimulus sequence could be generated using a fully analogue constant current driver and fed to the electrode. Measurement of the current delivered could be monitored and an impedance estimate of the electrode made. Noise and potential for interference was measured for both systems i.e. for both electrode and MEG recordings. Two separate MEG installations were tested for compatibility, a CTF and an Elekta system. Results Wide-band electrode recordings show a thermal noise commensurate with the electrode impedance. High quality recordings could be obtained from mechanoreceptive afferents originating in the hand. There was some electrical interference (50 Hz and lighting related) on the electrode recordings in the CTF, but this did not prevent successful microneurography. No interference was observed on the Elekta system. At stimulus levels usually used (

Published
2018

16. Imaging the cortical responses to quantised touch

Author

O'Neill, George, Wessberg, Johan, Watkins, Roger, Ackerley, Rochelle, Barratt, Eleanor, Glover, Paul, Sengupta, Ayan, Brookes, Matthew, Francis, Susan, School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Göteborgs Universitet (GU), Neurosciences sensorielles et cognitives (NSC), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), and Ackerley, Rochelle

Subjects
[SCCO.NEUR]Cognitive science/Neuroscience, [SCCO.NEUR] Cognitive science/Neuroscience
Abstract

International audience; BackgroundWithin the glabrous skin, touch is supported by mechanoreceptors, with most haptic sensations resulting from a combination of different mechanoreceptors being employed. These receptors can be broken down into two groups, those that are slowly-adapting (SAI, SAII), which detect changes in skin deformation (e.g. pressure), and those that are fast-adapting (FAI, FAII), which detect rapid fluctuations (e.g. vibration). A lot is known about the different receptors’ properties within the peripheral nervous system, but how these individual sensations are represented in the brain in humans has been investigated less. Here, we introduce the first known attempt to image these discrete responses using magnetoencephalography (MEG). Methods 9 participants volunteered to undergo a microneurography procedure, where a tungsten electrode was placed within the median nerve, and single mechanoreceptive afferents were recorded from. Once a single afferent had been identified, the participant received a small current (~5 μA, consisting of 60 200 μs pulses over 1 s) down the electrode to electrically-stimulate the same afferent identified physiologically. If there was a match, the participant underwent a scan using a 275-channel CTF MEG system in a synthetic 3rd order gradiometer configuration, where the same 1 s stimulation was repeated 80 times with ~10 s inter trial intervals. Data were frequency filtered between 13-30 Hz, and source localised using a beamformer and a 3-shell boundary element model. Pseudo-T statistical images were generated contrasting oscillatory power during stimulation against an epoch 8-9 seconds after stimulation. Results Across the cohort we recorded MEG data stimulating 19 mechanoreceptive afferents, and after quality control checks, we were left with 16 units (10 FAI, perceived sensation: point-like vibration; 5 SAI, perceived sensation: point-like pressure; 1 FAII, perceived sensation: diffuse vibration). A group analysis of the 10 FAI afferents show a significant event-related decrease in 13-30 Hz power during stimulation, with the largest change in power occurring in the postcentral gyrus. Permutation testing of the individual receptors’ images reveal that 8/10 of these receptors had significant reductions in power, which were all in spatial agreement with each other.Discussion In this investigation we have shown that it is possible to detect the spatial, temporal, and spectral properties of the cortical representations of individual mechanoreceptive afferents using MEG. Future investigations will interrogate how different afferent types manifest in the cortex in response to stimulation.

Published
2018

17. Van der Waals epitaxy of two-dimensional single-layer h-BN on graphite by molecular beam epitaxy: Electronic properties and band structure

Author

Pierucci, Deborah, Zribi, Jihene, Henck, Hugo, Chaste, Julien, Silly, Mathieu g., Bertran, François, Le fevre, P., GIL, Bernard, Summerfeld, Alex, Beton, Peter, Novikov, Sergei, CASSABOIS, Guillaume, Rault, Julien, Ouerghi, Abdelkarim, CELLS ALBA, Cerdanyola Del Valles 08390, Spain, Centre de Nanosciences et de Nanotechnologies [Marcoussis] (C2N), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Laboratoire de photonique et de nanostructures (LPN), LABEX GANEX, ANR-11-LABX-0014,GANEX,Réseau national sur GaN(2011), and Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)

Subjects
Boron nitride, Condensed Matter - Materials Science, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Materials Science (cond-mat.mtrl-sci), FOS: Physical sciences
Abstract

We report on the controlled growth of h-BN/graphite by means of molecular beam epitaxy (MBE). X-ray photoelectron spectroscopy (XPS) suggests an interface without any reaction or intermixing, while the angle resolved photoemission spectroscopy (ARPES) measurements show that the h-BN layers are epitaxially aligned with graphite. A well-defined band structure is revealed by ARPES measurement, reflecting the high quality of the h-BN films. The measured valence band maximum (VBM) located at 2.8 eV below the Fermi level reveals the presence of undoped h-BN films (band gap ~ 6 eV). These results demonstrate that, although only weak van der Waals interactions are present between h-BN and graphite, a long range ordering of h-BN can be obtained even on polycrystalline graphite via van der Waals epitaxy, offering the prospect of large area, single layer h-BN., 9 pages, 4 figures SI 5 pages 2 figures

Published
2018
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18. The Dust and [C ii] Morphologies of Redshift ∼4.5 Sub-millimeter Galaxies at ∼200 pc Resolution:The Absence of Large Clumps in the Interstellar Medium at High-redshift

Author

Novak, Mladen, Sargent, Mark, Herrera-Camus, R., Belli, S., Übler, H., Shimizu, T., Davies, R., Sturm, E., Colina, L., Cunha, E. da, Rybak, M., Venemans, B., Brandt, W., Rivera, G. Calistro, Knudsen, K., Werf, P. van der, Freundlich, J., Combes, F., Tacconi, L., Genzel, R., Garcia-Burillo, S., Bolatto, A., Lilly, S., Salomé, P., Bicalho, I., Boissier, J., Boone, F., Bouché, N., Bournaud, F., Burkert, A., Carollo, M., Cooper, M., Feruglio, C., Förster Schreiber, N., Juneau, S., Lippa, M., Lutz, D., Naab, T., Renzini, A., Saintonge, A., Sternberg, A., Weiner, B., Weiß, A., Wuyts, S., Bouwens, Rychard, Brinchmann, Jarle, Maseda, Michael, Matthee, Jorryt, Schaye, Joop, Schouws, Sander, Pavesi, Riccardo, Le Fèvre, Olivier, Yang, C., Gavazzi, R., Beelen, A., Lehnert, M., Gao, Y., Barcos-Muñoz, L., Neri, R., Fu, H., González-Alfonso, E., Michałowski, M., Nightingale, J., Pérez-Fournon, I., Shao, Yali, Wang, Ran, Li, Jianan, Fan, Xiaohui, Jiang, Linhua, Strauss, Michael, Menten, Karl, Ma, Jingzhe, Cooray, Asantha, Nayyeri, Hooshang, Brown, Arianna, Ghotbi, Noah, Oteo, Ivan, Duivenvoorden, Steven, Greenslade, Joshua, Clements, David, Battisti, Andrew, Ashby, Matthew, Perez-Fournon, Ismael, Oliver, Seb, Eales, Stephen, Negrello, Mattia, Dye, Simon, Dunne, Loretta, Omont, Alain, Serjeant, Stephen, Maddox, Steve, Valiante, Elisabetta, Pillepich, Annalisa, Nelson, Dylan, Cunha, Elisabete da, Diemer, Benedikt, González-López, Jorge, Hernquist, Lars, Marinacci, Federico, Rix, Hans-Walter, Swinbank, Mark, Vogelsberger, Mark, Werf, Paul van der, Yung, L., Aravena, Manuel, Decarli, Roberto, Gónzalez-López, Jorge, Boogaard, Leindert, Carilli, Chris, Popping, Gergö, Assef, Roberto, Bacon, Roland, Bauer, Franz Erik, Bouwens, Richard, Contini, Thierry, Cortes, Paulo, Da Cunha, Elisabete, Daddi, Emanuele, Díaz-Santos, Tanio, Elbaz, David, Inami, Hanae, Fevre, Olivier Le, Magnelli, Benjamin, Oesch, Pascal, Riechers, Dominik, Somerville, Rachel, Uzgil, Bade, Wagg, Jeff, Wisotzki, Lutz, Gullberg, B., Swinbank, A. Mark, Smail, Ian, Biggs, A., Bertoldi, Frank, Breuck, C. De, Chapman, S., Chen, Chian-Chou, Cooke, E., Coppin, K., Cox, Pierre, Dannerbauer, H., Dunlop, J., Edge, A., Farrah, D., Geach, J., GREVE, T., Hodge, Jacqueline, Ibar, E., Ivison, Rob, Karim, A., Schinnerer, E., Scott, Douglas, Simpson, J., Stach, S., Thomson, A., Van Der Werf, Paul, Walter, Fabian, Wardlow, Julie, Weiss, Axel, 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), Max Planck Institute for Extraterrestrial Physics (MPE), Max-Planck-Gesellschaft, Department of Physics, Durham University, Racah Institute of Physics, The Hebrew University of Jerusalem (HUJ), 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), Observatorio Astronomico Nacional [Madrid] (OAN), Instituto Geografico Nacional (IGN), Department of Astronomy [College Park], University of Maryland [College Park], University of Maryland System-University of Maryland System, AUTRES, 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-Seine-Université Paris-Seine-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Interactions Hôtes-Pathogènes-Environnements (IHPE), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Perpignan Via Domitia (UPVD), Institut Interdisciplinaire d'Innovation Technologique (3IT), Université de Sherbrooke [Sherbrooke], Universitätssternwarte der Ludwig-Maximiliansuniversität, Ludwig-Maximiliansuniversität, Institute for Astronomy [Zürich], Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), University of São Paulo, INAF - Osservatorio Astronomico di Roma (OAR), Istituto Nazionale di Astrofisica (INAF), Steward observatory, University of Arizona, Max-Planck-Institut für Extraterrestrische Physik (MPE), Institut of Physics - Riga, Latvian Academy of Sciences, Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Guangzhou Marine Geological Survey, Ministry of Land and Resources (MLR), Physics Department [Santa Barbara], University of California [Santa Barbara] (UCSB), University of California-University of California, 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), Galaxies, Etoiles, Physique, Instrumentation (GEPI), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL), Milieux aquatiques, écologie et pollutions (UR MALY), Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Universidad de Alcalá - University of Alcalá (UAH), Instituto de Astrofisica de Canarias (IAC), Institute of Plant and Environment Protection, Beijing Academy of Agriculture and Forestry Sciences, Arizona State University [Tempe] (ASU), Max-Planck-Institut für Radioastronomie (MPIFR), California Institute of Technology (CALTECH), Astronomy Centre, University of Sussex, University of Massachusetts [Amherst] (UMass Amherst), University of Massachusetts System (UMASS), School of Physics and Astronomy [Cardiff], Cardiff University, Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Moléculaires de Marseille (ISM2), Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU), School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University [Cambridge]-Smithsonian Institution, Max-Planck-Institut für Astronomie (MPIA), Institute for Computational Cosmology (ICC), National Radio Astronomy Observatory [Socorro] (NRAO), National Radio Astronomy Observatory (NRAO), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS), Département d'Astrophysique (ex SAP) (DAP), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Yale Center for Astronomy and Astrophysics (YCAA), Yale University [New Haven], Cornell University, Rutgers University, Astrophysikalisches Institut Potsdam (AIP), Institute of Computational Cosmology, Argelander Institute for Astronomy (AlfA), Rheinische Friedrich-Wilhelms-Universität Bonn, Université de Lyon, SUPA, Institute for Astronomy, University of Edinburgh, University of Wales, Department of Physics [Blacksburg], Virginia Tech [Blacksburg], Space Plasma Group, Astronomy Unit [London] (AU), Queen Mary University of London (QMUL)-Queen Mary University of London (QMUL), Royal Observatory Edinburgh (ROE), Interactions et dynamique des environnements de surface (IDES), CLRC Daresbury, SFTC, Centre de Recherches sur la Cognition Animale (CRCA), Institut des sciences du cerveau de Toulouse. (ISCT), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Pacific Northwest National Laboratory (PNNL), Department of Astronomy, University of California [Irvine] (UCI), Centre de Biologie Intégrative (CBI), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut des sciences du cerveau de Toulouse. (ISCT), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse - Jean Jaurès (UT2J)-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), 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), 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), Université de Perpignan Via Domitia (UPVD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), and Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO), FOS: Physical sciences, galaxies [submillimeter], Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, 0103 physical sciences, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, ComputingMilieux_MISCELLANEOUS, evolution [galaxies], Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], ISM [galaxies], 010308 nuclear & particles physics, Resolution (electron density), Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Redshift, Galaxy, Interstellar medium, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics of Galaxies (astro-ph.GA), Millimeter, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

We present deep high resolution (0.03", 200pc) ALMA Band 7 observations covering the dust continuum and [CII] $\lambda157.7\mu$m emission in four $z\sim4.4-4.8$ sub-millimeter galaxies (SMGs) selected from the ALESS and AS2UDS surveys. The data show that the rest-frame 160$\mu$m (observed 345 GHz) dust emission is consistent with smooth morphologies on kpc scales for three of the sources. One source, UDS47.0, displays apparent substructure but this is also consistent with a smooth morphology, as indicated by simulations showing that smooth exponential disks can appear clumpy when observed at high angular resolution (0.03") and depth of these observations ($\sigma_{345\text{GHz}} \sim27-47\mu$Jy beam$^{-1}$). The four SMGs are bright [CII] emitters, and we extract [CII] spectra from the high resolution data, and recover $\sim20-100$% of the [CII] flux and $\sim40-80$% of the dust continuum emission, compared to the previous lower resolution observations. When tapered to 0.2" resolution our maps recover $\sim80-100$% of the continuum emission, indicating that $\sim60$% of the emission is resolved out on $\sim200$pc scales. We find that the [CII] emission in high-redshift galaxies is more spatially extended than the rest-frame 160$\mu$m dust continuum by a factor of $1.6\pm0.4$. By considering the $L_{\text{[CII]}}$/$L_{\text{FIR}}$ ratio as a function of the star-formation rate surface density ($\Sigma_{\text{SFR}}$) we revisit the [CII] deficit, and suggest that the decline in the $L_{\text{[CII]}}$/$L_{\text{FIR}}$ ratio as a function of $\Sigma_{\text{SFR}}$ is consistent with local processes. We also explore the physical drivers that may be responsible for these trends and can give rise to the properties found in the densest regions of SMGs., Comment: 15 pages, 6 figures, 4 tables, accepted for publication in ApJ

Published
2018
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19. The effects of climate change on high mountain environments : evolution of mountaineering routes in the Mont Blanc massif over half a century

Author

Mourey, Jacques, Marcuzzi, Matteo, Ravanel, Ludovic, Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), and EDYTEM, Océane Giorda

Subjects
[SDE] Environmental Sciences, [SDE]Environmental Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2018

20. Constraining screened fifth forces with the electron magnetic moment

Author

Leong Khim Wong, Anne-Christine Davis, Philippe Brax, Benjamin Elder, Institut de Physique Théorique - UMR CNRS 3681 (IPHT), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Department of Applied Mathematics and Theoretical Physics (DAMTP), University of Cambridge [UK] (CAM), School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), European Project: 690575,H2020,H2020-MSCA-RISE-2015,InvisiblesPlus(2016), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), De Laborderie, Emmanuelle, InvisiblesPlus - InvisiblesPlus - - H20202016-02-01 - 2020-01-31 - 690575 - VALID, Institut de Physique Théorique - UMR CNRS 3681 ( IPHT ), and Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay-Centre National de la Recherche Scientifique ( CNRS )

Subjects
chameleon, electron: magnetic moment, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Atomic Physics (physics.atom-ph), [ PHYS.ASTR ] Physics [physics]/Astrophysics [astro-ph], Physics beyond the Standard Model, FOS: Physical sciences, Parameter space, 01 natural sciences, correction: quantum, Physics - Atomic Physics, Gravitation, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Theoretical physics, High Energy Physics - Phenomenology (hep-ph), 0103 physical sciences, [ PHYS.PHYS.PHYS-GEN-PH ] Physics [physics]/Physics [physics]/General Physics [physics.gen-ph], numerical calculations, 010306 general physics, Quantum, Physics, new physics, precision measurement, 010308 nuclear & particles physics, screening, Fifth force, Scalar (physics), solar system, Electron magnetic dipole moment, vacuum system, [PHYS.PHYS.PHYS-GEN-PH]Physics [physics]/Physics [physics]/General Physics [physics.gen-ph], fifth force, field theory: scalar, High Energy Physics - Phenomenology, [PHYS.ASTR.CO] Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], gravitation, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], [ PHYS.HPHE ] Physics [physics]/High Energy Physics - Phenomenology [hep-ph], [PHYS.ASTR] Physics [physics]/Astrophysics [astro-ph], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Phenomenology (particle physics), Astrophysics - Cosmology and Nongalactic Astrophysics, symmetron
Abstract

Chameleon and symmetron theories serve as archetypal models for how light scalar fields can couple to matter with gravitational strength or greater, yet evade the stringent constraints from classical tests of gravity on Earth and in the Solar System. In this work, we investigate how a precision measurement of the electron magnetic moment places meaningful constraints on both chameleons and symmetrons. Two effects are identified: First, virtual chameleons and symmetrons run in loops to generate quantum corrections to the intrinsic value of the magnetic moment; a common process widely considered in the literature for many scenarios beyond the Standard Model. A second effect, however, is unique to scalar fields that exhibit screening. A scalar bubblelike profile forms inside the experimental vacuum chamber and exerts a fifth force on the electron, leading to a systematic shift in the experimental measurement. In quantifying this latter effect, we present a novel approach that combines analytic arguments and a small number of numerical simulations to solve for the bubblelike profile quickly for a large range of model parameters. Taken together, both effects yield interesting constraints in complementary regions of parameter space. While the constraints we obtain for the chameleon are largely uncompetitive with those in the existing literature, this still represents the tightest constraint achievable yet from an experiment not originally designed to search for fifth forces. We break more ground with the symmetron, for which our results exclude a large and previously unexplored region of parameter space. Central to this achievement are the quantum correction terms, which are able to constrain symmetrons with masses in the range $\mu \in [10^{-3.88},10^8]\,\text{eV}$, whereas other experiments have hitherto only been sensitive to 1 or 2 orders of magnitude at a time., Comment: 18 pages + appendices, 12 figures. Abstract abridged for arXiv submission. v2: Minor typos corrected to match PRD version

Published
2018
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21. Nano-contact microscopy of supracrystals

Author

Nicolas Goubet, Marie-Paule Pileni, Philip Moriarty, Ioannis Lekkas, Adam Sweetman, School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), De la Molécule aux Nanos-objets : Réactivité, Interactions et Spectroscopies (MONARIS), Institut de Chimie du CNRS (INC)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Electronique et nanoPhotonique Organique (LEPO), Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, and Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, General Physics and Astronomy, scanning probe microscopy, Nanotechnology, 02 engineering and technology, lcsh:Chemical technology, 01 natural sciences, lcsh:Technology, Full Research Paper, Scanning probe microscopy, Condensed Matter::Materials Science, non-contact atomic force microscopy, 0103 physical sciences, Microscopy, General Materials Science, lcsh:TP1-1185, Electrical and Electronic Engineering, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, 010306 general physics, lcsh:Science, Nanoscopic scale, Quantum tunnelling, point contact imaging, supracrystal, lcsh:T, nanoparticle, Resolution (electron density), dynamic force microscopy, Colloidal crystal, 021001 nanoscience & nanotechnology, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, lcsh:QC1-999, Nanoscience, Nanocrystal, Chemical physics, lcsh:Q, 0210 nano-technology, Non-contact atomic force microscopy, lcsh:Physics
Abstract

Background: Highly ordered three-dimensional colloidal crystals (supracrystals) comprised of 7.4 nm diameter Au nanocrystals (with a 5% size dispersion) have been imaged and analysed using a combination of scanning tunnelling microscopy and dynamic force microscopy.Results: By exploring the evolution of both the force and tunnel current with respect to tip–sample separation, we arrive at the surprising finding that single nanocrystal resolution is readily obtained in tunnelling microscopy images acquired more than 1 nm into the repulsive (i.e., positive force) regime of the probe–nanocrystal interaction potential. Constant height force microscopy has been used to map tip–sample interactions in this regime, revealing inhomogeneities which arise from the convolution of the tip structure with the ligand distribution at the nanocrystal surface.Conclusion: Our combined STM–AFM measurements show that the contrast mechanism underpinning high resolution imaging of nanoparticle supracrystals involves a form of nanoscale contact imaging, rather than the through-vacuum tunnelling which underpins traditional tunnelling microscopy and spectroscopy.

Published
2015
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22. Magnetic anisotropy in antiferromagnetic hexagonal MnTe

Author

Valentine V. Volobuev, J. Godinho, Tomas Jungwirth, Václav Holý, Alexander B. Shick, Joerg Grenzer, Helena Reichlova, Thomas Wagner, S. Y. Martin, Eric Ressouche, Dominik Kriegner, Karel Výborný, Wolfgang Schmidt, G. Springholz, Jörg Wunderlich, Institute of Physics [Prague], Czech Academy of Sciences [Prague] (CAS), Charles University [Prague] (CU), Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Magnétisme et Diffusion Neutronique (MDN), Modélisation et Exploration des Matériaux (MEM), Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Hitachi Cambridge Laboratory [University of Cambridge], Hitachi, Ltd-University of Cambridge [UK] (CAM), SPINtronique et TEchnologie des Composants (SPINTEC), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Johannes Kepler University Linz [Linz] (JKU), School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), University of Cambridge [UK] (CAM)-Hitachi, Ltd, and Johannes Kepler Universität Linz - Johannes Kepler University Linz [Autriche] (JKU)

Subjects
Materials science, Magnetometer, Neutron diffraction, FOS: Physical sciences, 02 engineering and technology, 01 natural sciences, law.invention, Condensed Matter::Materials Science, law, MOLECULAR-BEAM EPITAXY, 0103 physical sciences, Antiferromagnetism, ddc:530, 010306 general physics, Anisotropy, TEMPERATURE, Condensed Matter - Materials Science, Spintronics, Magnetic moment, Condensed matter physics, MEMORY, Materials Science (cond-mat.mtrl-sci), 021001 nanoscience & nanotechnology, Magnetic field, Magnetic anisotropy, NEUTRON-DIFFRACTION, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], MANGANESE TELLURIDE, THERMAL-EXPANSION, 0210 nano-technology, BEHAVIOR, FILM
Abstract

Antiferromagnetic hexagonal MnTe is a promising material for spintronic devices relying on the control of antiferromagnetic domain orientations. Here we report on neutron diffraction, magnetotransport, and magnetometry experiments on semiconducting epitaxial MnTe thin films together with density functional theory (DFT) calculations of the magnetic anisotropies. The easy axes of the magnetic moments within the hexagonal basal plane are determined to be along $\left$ directions. The spin-flop transition and concomitant repopulation of domains in strong magnetic fields is observed. Using epitaxially induced strain the onset of the spin-flop transition changes from $\sim2$~T to $\sim0.5$~T for films grown on InP and SrF$_2$ substrates, respectively., 9 pages, 7 figures

Published
2017
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23. Zero-dimensional Zener Tunnelling and Plasmon Resonances due to N- and H- Incorporation in the Narrow Gap InAs

Author

Di Paola, D. M., Velichko, A. V., Bomers, M., Balakrishnan, N., Makarovsky, O., Capizzi, M., Polimeni, A., Kesaria, M., Krier, A., Eaves, L., Thierry Taliercio, Patanè, A., Institut d’Electronique et des Systèmes (IES), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), McMaster University [Hamilton, Ontario], School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Composants à Nanostructure pour le moyen infrarouge (NANOMIR), and Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
ComputingMilieux_MISCELLANEOUS, [SPI.TRON]Engineering Sciences [physics]/Electronics
Abstract

International audience

Published
2017

24. The implications of the surprising existence of a large, massive CO disk in a distant protocluster

Author

Dannerbauer, H., Lehnert, M. D., Emonts, B., Ziegler, B., Altieri, B., De, Breuck C., Hatch, N., Kurk, J. D., Matiz, T., Miley, G., Narayanan, D., Norris, R. P., Overzier, R., Rottgering, H. J. A., Sargent, M., Seymour, N., Valtchanov, I., Wylezalek, D., Kodama, Tadayuki, Koyama, Yusei, Tanaka, Masaomi, Instituto de Astrofisica de Canarias (IAC), Dpto Astrofísica, Universidad de La Laguna [Tenerife - SP] (ULL), Institut für Astrophysik [Wien], Universität Wien, Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Centro de Astrobiologia [Madrid] (CAB), Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Herschel Science Centre, European Space Agency (ESA), European Southern Observatory (ESO), School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Optical and Infrared Astronomy Division, National Astronomical Observatory of Japan (NAOJ), Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency [Sagamihara] (JAXA), Max-Planck-Institut für Extraterrestrische Physik (MPE), Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Department of Astronomy [Gainesville] (UF|Astro), University of Florida [Gainesville] (UF), CSIRO Astronomy and Space Science, Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), Western Sydney University, Observatorio Nacional [Rio de Janeiro], Astronomy Centre [Brighton], University of Sussex, International Center for Radio Astronomy Research, Curtin University [Perth], Planning and Transport Research Centre (PATREC)-Planning and Transport Research Centre (PATREC), Department of Physics and Astronomy [Baltimore], and Johns Hopkins University (JHU)

Subjects
submillimeter: galaxies, galaxies: clusters: individual: MRC1138-262, Field (physics), Radio galaxy, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, law.invention, Telescope, law, galaxies: high-redshift, galaxies: individual: HAE229, 0103 physical sciences, Cluster (physics), Surface brightness, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, QB, Physics, galaxies: clusters: individual: MRC 1138 / 262, 010308 nuclear & particles physics, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Galaxy, Ram pressure, Space and Planetary Science, galaxies: clusters: individual: MRC 1138, Astrophysics of Galaxies (astro-ph.GA), Optical emission spectroscopy, galaxies: evolution, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], galaxies: ISM
Abstract

著者人数: 21名, Accepted: 2017-07-03, 資料番号: SA1170133000

Published
2017
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25. The direct-to-indirect band gap crossover in two-dimensional van der Waals Indium Selenide crystals

Author

Maciej R. Molas, Zakhar D. Kovalyuk, Viktor Zólyomi, Oleg Makarovsky, Xi Chen, Vladimir I. Fal'ko, Amalia Patanè, Garry W. Mudd, Laurence Eaves, Marek Potemski, K. Nogajewski, Zakhar R. Kudrynskyi, Go Yusa, Laboratoire national des champs magnétiques intenses - Grenoble (LNCMI-G ), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Laboratoire Kastler Brossel (LKB (Jussieu)), Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Université Pierre et Marie Curie - Paris 6 (UPMC)-Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, Band gap, Chalcogenide, Exciton, Physics::Optics, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Article, symbols.namesake, chemistry.chemical_compound, National Graphene Institute, Electronic band structure, ComputingMilieux_MISCELLANEOUS, [PHYS.COND.CM-MSQHE]Physics [physics]/Condensed Matter [cond-mat]/Mesoscopic Systems and Quantum Hall Effect [cond-mat.mes-hall], Multidisciplinary, Condensed matter physics, business.industry, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Semiconductor, chemistry, ResearchInstitutes_Networks_Beacons/national_graphene_institute, symbols, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Direct and indirect band gaps, Density functional theory, van der Waals force, 0210 nano-technology, business
Abstract

The electronic band structure of van der Waals (vdW) layered crystals has properties that depend on the composition, thickness and stacking of the component layers. Here we use density functional theory and high field magneto-optics to investigate the metal chalcogenide InSe, a recent addition to the family of vdW layered crystals, which transforms from a direct to an indirect band gap semiconductor as the number of layers is reduced. We investigate this direct-to-indirect bandgap crossover, demonstrate a highly tuneable optical response from the near infrared to the visible spectrum with decreasing layer thickness down to 2 layers, and report quantum dot-like optical emissions distributed over a wide range of energy. Our analysis also indicates that electron and exciton effective masses are weakly dependent on the layer thickness and are significantly smaller than in other vdW crystals. These properties are unprecedented within the large family of vdW crystals and demonstrate the potential of InSe for electronic and photonic technologies.

Published
2016
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26. Quasi-normal modes and fermionic vacuum decay around a Kerr black hole

Author

Peter Millington, Antonin Coutant, School of Mathematical Sciences [Nottingham], University of Nottingham, UK (UON), and School of Physics and Astronomy [Nottingham]

Subjects
High Energy Physics - Theory, Condensed Matter::Quantum Gases, Physics, Physics and Astronomy (miscellaneous), [PHYS.HTHE]Physics [physics]/High Energy Physics - Theory [hep-th], 010308 nuclear & particles physics, FOS: Physical sciences, General Relativity and Quantum Cosmology (gr-qc), Fermion, black holes, Dirac fields, quasi-normal modes, vacuum decay, 01 natural sciences, Instability, General Relativity and Quantum Cosmology, Supercritical fluid, High Energy Physics - Theory (hep-th), Rotating black hole, Normal mode, Quantum electrodynamics, 0103 physical sciences, [PHYS.GRQC]Physics [physics]/General Relativity and Quantum Cosmology [gr-qc], 010306 general physics, ComputingMilieux_MISCELLANEOUS, False vacuum, Fermi Gamma-ray Space Telescope
Abstract

We analyze the instability of the non-rotating fermion vacuum in Kerr spacetimes. We describe how the co-rotating Fermi sea is formed as a result of a spontaneous vacuum decay. Most significantly, and drawing upon intuition gained from analogous electrodynamic processes in supercritical fields, we show that this decay process is encoded entirely in a subset of quasi-normal fermion modes., Comment: 25 pages, 2 figures. V2: contains additional minor clarifications, along with corrections to Fig. 2, and Eqs. (45), (46) and (53), which were overlooked in the published version. Selected for a CQG+ insight article

Published
2019
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27. The DESI Experiment Part I: Science,Targeting, and Survey Design

Author

Aghamousa, Amir, Aguilar, Jessica, Ahlen, Steve, Alam, Shadab, Allen, Lori E., Prieto, Carlos Allende, Annis, James, Bailey, Stephen, Balland, Christophe, Ballester, Otger, Baltay, Charles, Beaufore, Lucas, Bebek, Chris, Beers, Timothy C., Bell, Eric F., Bernal, José Luis, Besuner, Robert, Beutler, Florian, Blake, Chris, Bleuler, Hannes, Blomqvist, Michael, Blum, Robert, Bolton, Adam S., Briceno, Cesar, Brooks, David, Brownstein, Joel R., Buckley-Geer, Elizabeth, Burden, Angela, Burtin, Etienne, Busca, Nicolás G., Cahn, Robert N., Cai, Yan-Chuan, Cardiel-Sas, Laia, Carlberg, Raymond G., Carton, Pierre-Henri, Casas, Ricard, Castander, Francisco J., Cervantes-Cota, Jorge L., Claybaugh, Todd M., Close, Madeline, Coker, Carl T., Cole, Shaun, Comparat, Johan, Cooper, Andrew P., Cousinou, M. -C., Crocce, Martin, Cuby, Jean-Gabriel, Cunningham, Daniel P., Davis, Tamara M., Dawson, Kyle S., de La Macorra, Axel, de Vicente, Juan, Delubac, Timothée, Derwent, Mark, Dey, Arjun, Dhungana, Govinda, Ding, Zhejie, Doel, Peter, Duan, Yutong T., Ealet, Anne, Edelstein, Jerry, Eftekharzadeh, Sarah, Eisenstein, Daniel J., Elliott, Ann, Escoffier, Stephanie, Evatt, Matthew, Fagrelius, Parker, Fan, Xiaohui, Fanning, Kevin, Farahi, Arya, Farihi, Jay, Favole, Ginevra, Feng, Yu, Fernandez, Enrique, Findlay, Joseph R., Finkbeiner, Douglas P., Fitzpatrick, Michael J., Flaugher, Brenna, Flender, Samuel, Font-Ribera, Andreu, Forero-Romero, Jaime E., Fosalba, Pablo, Frenk, Carlos S., Fumagalli, Michele, Gaensicke, Boris T., Gallo, Giuseppe, Garcia-Bellido, Juan, Gaztanaga, Enrique, Fusillo, Nicola Pietro Gentile, Gerard, Terry, Gershkovich, Irena, Giannantonio, Tommaso, Gillet, Denis, Gonzalez-De-Rivera, Guillermo, Gonzalez-Perez, Violeta, Gott, Shelby, Graur, Or, Gutierrez, Gaston, Guy, Julien, Habib, Salman, Heetderks, Henry, Heetderks, Ian, Heitmann, Katrin, Hellwing, Wojciech A., Herrera, David A., Ho, Shirley, Holland, Stephen, Honscheid, Klaus, Huff, Eric, Hutchinson, Timothy A., Huterer, Dragan, Hwang, Ho Seong, Laguna, Joseph Maria Illa, Ishikawa, Yuzo, Jacobs, Dianna, Jeffrey, Niall, Jelinsky, Patrick, Jennings, Elise, Jiang, Linhua, Jimenez, Jorge, Johnson, Jennifer, Joyce, Richard, Jullo, Eric, Juneau, Stéphanie, Kama, Sami, Karcher, Armin, Karkar, Sonia, Kehoe, Robert, Kennamer, Noble, Kent, Stephen, Kilbinger, Martin, Kim, Alex G., Kirkby, David, Kisner, Theodore, Kitanidis, Ellie, Kneib, Jean-Paul, Koposov, Sergey, Kovacs, Eve, Koyama, Kazuya, Kremin, Anthony, Kron, Richard, Kronig, Luzius, Kueter-Young, Andrea, Lacey, Cedric G., Lafever, Robin, Lahav, Ofer, Lambert, Andrew, Lampton, Michael, Landriau, Martin, Lang, Dustin, Lauer, Tod R., Goff, Jean-Marc Le, Guillou, Laurent Le, van Suu, Auguste Le, Lee, Jae Hyeon, Lee, Su-Jeong, Leitner, Daniela, Lesser, Michael, Levi, Michael E., L'Huillier, Benjamin, Li, Baojiu, Liang, Ming, Lin, Huan, Linder, Eric, Loebman, Sarah R., Lukić, Zarija, Ma, Jun, Maccrann, Niall, Magneville, Christophe, Makarem, Laleh, Manera, Marc, Manser, Christopher J., Marshall, Robert, Martini, Paul, Massey, Richard, Matheson, Thomas, Mccauley, Jeremy, Mcdonald, Patrick, Mcgreer, Ian D., Meisner, Aaron, Metcalfe, Nigel, Miller, Timothy N., Miquel, Ramon, Moustakas, John, Myers, Adam, Naik, Milind, Newman, Jeffrey A., Nichol, Robert C., Nicola, Andrina, da Costa, Luiz Nicolati, Nie, Jundan, Niz, Gustavo, Norberg, Peder, Nord, Brian, Norman, Dara, Nugent, Peter, O'Brien, Thomas, Oh, Minji, Olsen, Knut A. G., Padilla, Cristobal, Padmanabhan, Hamsa, Padmanabhan, Nikhil, Palanque-Delabrouille, Nathalie, Palmese, Antonella, Pappalardo, Daniel, Paris, Isabelle, Park, Changbom, Patej, Anna, Peacock, John A., Peiris, Hiranya V., Peng, Xiyan, Percival, Will J., Perruchot, Sandrine, Pieri, Matthew M., Pogge, Richard, Pollack, Jennifer E., Poppett, Claire, Prada, Francisco, Prakash, Abhishek, Probst, Ronald G., Rabinowitz, David, Raichoor, Anand, Ree, Chang Hee, Refregier, Alexandre, Régal, Xavier, Reid, Beth, Reil, Kevin, Rezaie, Mehdi, Rockosi, Constance M., Roe, Natalie, Ronayette, Samuel, Roodman, Aaron, Ross, Ashley J., Ross, Nicholas P., Rossi, Graziano, Rozo, Eduardo, Ruhlmann-Kleider, Vanina, Rykoff, Eli S., Sabiu, Cristiano, Samushia, Lado, Sanchez, Eusebio, Sanchez, Javier, Schlegel, David J., Schneider, Michael, Schubnell, Michael, Secroun, Aurélia, Seljak, Uros, Seo, Hee-Jong, Serrano, Santiago, Shafieloo, Arman, Shan, Huanyuan, Sharples, Ray, Sholl, Michael J., Shourt, William V., Silber, Joseph H., Silva, David R., Sirk, Martin M., Slosar, Anze, Smith, Alex, Smoot, George F., Som, Debopam, Song, Yong-Seon, Sprayberry, David, Staten, Ryan, Stefanik, Andy, Tarlè, Gregory, Tie, Suk Sien, Tinker, Jeremy L., Tojeiro, Rita, Valdes, Francisco, Valenzuela, Octavio, Valluri, Monica, Vargas-Magaña, Mariana, Verde, Licia, Walker, Alistair R., Wang, Jiali, Wang, Yuting, Weaver, Benjamin A., Weaverdyck, Curtis, Wechsler, Risa H., Weinberg, David H., White, Martin, Yang, Qian, Yeche, Christophe, Zhang, Tianmeng, Zhao, Gong-Bo, Zheng, Yi, Zhou, Xu, Zhou, Zhimin, Zhu, Yaling, Zou, Hu, Zu, Ying, Korea Astronomy and Space Science Institute (KASI), Okayama University, University of California [Berkeley], University of California, National Optical Astronomy Observatory (NOAO), Instituto de Astrofisica de Canarias (IAC), Fermi National Accelerator Laboratory (Fermilab), Lawrence Berkeley National Laboratory [Berkeley] (LBNL), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE (UMR_7585)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Institut de Física d’Altes Energies [Barcelone] (IFAE), Universitat Autònoma de Barcelona (UAB), Yale University [New Haven], Ohio State University [Columbus] (OSU), The University of Notre Dame [Sydney], Department of Astronomy, University of Michigan, University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Institut de Ciencies del Cosmos (ICCUB), Universitat de Barcelona (UB), Space Sciences Laboratory [Berkeley] (SSL), University of California-University of California, University of Portsmouth, University of British Columbia (UBC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Cerro Tololo Inter-American Observatory, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, APC - Cosmologie, AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Institute for Astronomy [Edinburgh] (IfA), University of Edinburgh, Department of Astronomy & Astrophysics [University of Toronto], University of Toronto, Institut de Ciencies de l'Espai [Barcelona] (ICE-CSIC), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Carreterra Mexico-Toluca, Department of Physics [Durham University], Durham University, Department of Astronomy, The Ohio State University, Departamento de FisicaTeorica e IFT-UAM/CSIC, Universidad Autonoma de Madrid (UAM), Institute for Computational Cosmology (ICC), Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Universidad Nacional Autónoma de México (UNAM), Department of Applied Physics, Departamento de Fisica Aplicada [Granada], Universidad de Granada (UGR)-Universidad de Granada (UGR), University College of London [London] (UCL), University of Wyoming (UW), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University [Cambridge]-Smithsonian Institution, Arizona State University [Tempe] (ASU), Department of Information Engineering, Zhejiang University of Technology, Zhejiang University of Technology, Institute for Astronomy [Honolulu], University of Hawai‘i [Mānoa] (UHM), Università degli Studi di Milano-Bicocca [Milano] (UNIMIB), Departamento de Fisica Teorica, Institute of Cosmology & Gravitation [Portsmouth], Carnegie Mellon University [Pittsburgh] (CMU), NASA Goddard Space Flight Center (GSFC), Korea Institute for Advanced Study (KIAS), Department of Physics and Astronomy [Irvine], University of California [Irvine] (UCI), Department of Physics, University of California, University of California [Los Angeles] (UCLA), Institute of Astronomy [Cambridge], University of Cambridge [UK] (CAM), Institute of Cosmology & Gravitation, Dennis Sciama Building, University of Portsmouth, Observatoire de Haute-Provence (OHP), Institut Pythéas (OSU PYTHEAS), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Center for Cosmology & AstroParticle Physics, California Institute of Technology (CALTECH), Department of Physics and Astronomy [Pittsburgh], University of Pittsburgh (PITT), Pennsylvania Commonwealth System of Higher Education (PCSHE)-Pennsylvania Commonwealth System of Higher Education (PCSHE), Institute for Astronomy [Zürich], Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Department of Physics [Durham], University of New Hampshire (UNH), University of Waterloo [Waterloo], Universität Zürich [Zürich] = University of Zurich (UZH), Department of Astronomy and Space Science [Sejong University], Sejong University, Department of Physics [Oxford], University of Oxford [Oxford], Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), Department of Physics [Ann Arbor], University of St Andrews [Scotland], University of Science and Technology of China [Hefei] (USTC), Department of Computer Science and Engineering [Minneapolis], University of Minnesota [Twin Cities] (UMN), University of Minnesota System-University of Minnesota System, Karlsruhe Institute of Technology (KIT), National University of Defense Technology [China], DESI Collaboration, University of California [Berkeley] (UC Berkeley), University of California (UC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), University of California (UC)-University of California (UC), 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), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Universidad Autónoma de Madrid (UAM), Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM), Universidad de Granada = University of Granada (UGR)-Universidad de Granada = University of Granada (UGR), Harvard University-Smithsonian Institution, Università degli Studi di Milano-Bicocca = University of Milano-Bicocca (UNIMIB), University of California [Irvine] (UC Irvine), University of Oxford, and Escoffier, Stephanie

Subjects
[PHYS.ASTR.IM]Physics [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], Astrophysics::Cosmology and Extragalactic Astrophysics, [PHYS.ASTR.IM] Physics [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], Astrophysics::Galaxy Astrophysics
Abstract

DESI (Dark Energy Spectroscopic Instrument) is a Stage IV ground-based dark energy experiment that will study baryon acoustic oscillations (BAO) and the growth of structure through redshift-space distortions with a wide-area galaxy and quasar redshift survey. To trace the underlying dark matter distribution, spectroscopic targets will be selected in four classes from imaging data. We will measure luminous red galaxies up to $z=1.0$. To probe the Universe out to even higher redshift, DESI will target bright [O II] emission line galaxies up to $z=1.7$. Quasars will be targeted both as direct tracers of the underlying dark matter distribution and, at higher redshifts ($ 2.1 < z < 3.5$), for the Ly-$\alpha$ forest absorption features in their spectra, which will be used to trace the distribution of neutral hydrogen. When moonlight prevents efficient observations of the faint targets of the baseline survey, DESI will conduct a magnitude-limited Bright Galaxy Survey comprising approximately 10 million galaxies with a median $z\approx 0.2$. In total, more than 30 million galaxy and quasar redshifts will be obtained to measure the BAO feature and determine the matter power spectrum, including redshift space distortions.

Published
2016

28. The luminosity-metallicity relation in the local Universe from the 2dF Galaxy Redshift Survey

Author

Thierry Contini, Steve Maddox, Mustapha Mouhcine, Ian Lewis, F. Lamareille, Laboratoire d'Astrophysique de l'Observatoire Midi-Pyrénées (LATT), 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), 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), Observatoire de Paris - Site de Paris (OP), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS), School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Observatoire astronomique de Strasbourg (OAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Departement of Physics, University of Oxford [Oxford], 2dF, Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - 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), 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), and University of Oxford

Subjects
abundances -galaxies, Astrophysics::High Energy Astrophysical Phenomena, Metallicity, media_common.quotation_subject, Milieu interstellaire, FOS: Physical sciences, Spectroscopie, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Luminosity, Astronomie extragalactique, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astronomie-astrophysique, Analyse du rayonnement électromagnétique, 0103 physical sciences, galaxies, Emission spectrum, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Cosmologie, media_common, Physics, 2dF Galaxy Redshift Survey, Spiral galaxy, 010308 nuclear & particles physics, Astrophysics (astro-ph), Astronomy and Astrophysics, Galaxy, Universe, evolution -galaxies, Space and Planetary Science, Magnitude (astronomy), starburst
Abstract

We investigate the Luminosity-Metallicity (L-Z) relation in the local universe (z < 0.15) using spectra of 6387 star-forming galaxies extracted from the 2dF Galaxy Redshift Survey. This sample is by far the largest to date used to perform such a study. We distinguish star-forming galaxies from AGNs using "standard" diagnostic diagrams to build a homogeneous sample of starburst galaxies for the L-Z study. We propose new diagnostic diagrams using "blue" emission lines ([OII]3727, [OIII]5007 and Hbeta) only to discriminate starbursts from AGNs in intermediate-redshift (z > 0.3) galaxies. Oxygen-to-hydrogen (O/H) abundance ratios are estimated using the "strong-line" method, which relates the strength of bright emission lines (parameters R23 and O32) to O/H. We confirm the existence of the luminosity-metallicity relation over a large range of abundances (~ 2 dex) and luminosities (~ 9 magnitudes). We find a linear relation between the gas-phase oxygen abundance and both the "raw" and extinction-corrected absolute B-band magnitude with a rms of 0.27. A similar relation, with nearly the same scatter, is found in the R band. This relation is in good agreement with the one derived by Melbourne & Salzer (2002) using the KISS data. However, our L-Z relation is much steeper than previous determinations using samples of "normal" irregular and spiral galaxies. This difference seems to be primarily due to the choice of the galaxy sample used to investigate the L-Z relation rather than any systematic error affecting the O/H determination. We anticipate that this luminosity-metallicity relation will be used as the local "reference" for future studies of the evolution with cosmic time of fundamental galaxy scaling relations. (Abridged version)., 11 pages, 9 figures. Accepted for publication in MNRAS

Published
2016
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29. Red galaxies with pseudo-bulges in the SDSS: closer to disc galaxies or to classical bulges?

Author

Catarina Lobo, J. M. Gomes, Polychronis Papaderos, Sonia Anton, B. Ribeiro, School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Laboratoire Récepteurs et Canaux Ioniques Membranaires (RCIM), Université d'Angers (UA)-Institut National de la Recherche Agronomique (INRA), and Récepteurs et Canaux Ioniques Membranaires (RCIM)

Subjects
Physics, Stellar mass, 010308 nuclear & particles physics, Star formation, FOS: Physical sciences, Astronomy, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Disc galaxy, 01 natural sciences, Astrophysics - Astrophysics of Galaxies, Galaxy, Secular variation, Photometry (optics), Space and Planetary Science, Bulge, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Disc, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

Pseudo-bulges are expected to markedly differ from classical, quasi-monolithically forming bulges in their star formation history (SFH) and chemical abundance patterns. To test this simple expectation, we carry out a comparative structural and spectral synthesis analysis of 106 red, massive galaxies issued from the SDSS, subdivided into bulgeless, pseudo-bulge and classical bulge galaxies according to their photometric characteristics, and further obeying a specific selection to minimize uncertainties in the analysis and ensure an unbiased derivation and comparison of SFHs. Our 2D photometry analysis suggests that disks underlying pseudo-bulges typically have larger exponential scale lengths than bulgeless galaxies, despite similar integral disk luminosities. Spectral synthesis models of the stellar emission within the 3" SDSS fiber aperture reveal a clear segregation of bulgeless and pseudo-bulge galaxies from classical bulges on the luminosity-weighted planes of age-metallicity and mass-metallicity, though a large dispersion is observed within the two former classes. The secular growth of pseudo-bulges is also reflected upon their cumulative stellar mass as a function of time, which is shallower than that for classical bulges. Such results suggest that the centers of bulgeless and pseudo-bulge galaxies substantially differ from those of bulgy galaxies with respect to their SFH and chemical enrichment history, which likely points to different formation/assembly mechanisms., 18 pages, 12 figure, accepted for MNRAS

Published
2016
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30. Probing WIMP particle physics and astrophysics with direct detection and neutrino telescope data

Author

Bradley J. Kavanagh, Mattia Fornasa, Anne M. Green, Institut de Physique Théorique - UMR CNRS 3681 (IPHT), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), ERC, STFC, MF, CSD2009-00064, and String Theory (ITFA, IoP, FNWI)

Subjects
Nuclear and High Energy Physics, Particle physics, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Physics::Instrumentation and Detectors, Dark matter, Massive particle, Flux, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Cross section (physics), High Energy Physics - Phenomenology (hep-ph), WIMP, 0103 physical sciences, 010306 general physics, Physics, Annihilation, 010308 nuclear & particles physics, Astrophysics::Instrumentation and Methods for Astrophysics, High Energy Physics - Phenomenology, Weakly interacting massive particles, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], High Energy Physics::Experiment, Neutrino, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

With positive signals from multiple direct detection experiments it will, in principle, be possible to measure the mass and cross sections of weakly-interacting massive particle (WIMP) dark matter. Recent work has shown that, with a polynomial parameterisation of the WIMP speed distribution, it is possible to make an unbiased measurement of the WIMP mass, without making any astrophysical assumptions. However, direct detection experiments are not sensitive to low-speed WIMPs and, therefore, any model-independent approach will lead to a bias in the cross section. This problem can be solved with the addition of measurements of the flux of neutrinos from the Sun. This is because the flux of neutrinos produced from the annihilation of WIMPs which have been gravitationally captured in the Sun is sensitive to low-speed WIMPs. Using mock data from next-generation direct detection experiments and from the IceCube neutrino telescope, we show that the complementary information from IceCube on low-speed WIMPs breaks the degeneracy between the cross section and the speed distribution. This allows unbiased determinations of the WIMP mass and spin-independent and spin-dependent cross sections to be made, and the speed distribution to be reconstructed. We use two parameterisations of the speed distribution: binned and polynomial. While the polynomial parameterisation can encompass a wider range of speed distributions, this leads to larger uncertainties in the particle physics parameters., Comment: 24 pages, 13 figures. Corrected error in likelihood; changes to discussion of Benchmark C. Matches version accepted in PRD

Published
2015
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31. Imaging and Manipulation of Adsorbates Using Dynamic Force Microscopy

Author

Moriarty, Philip, Gauthier, Sebastien, School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Groupe NanoSciences (CEMES-GNS), Centre d'élaboration de matériaux et d'études structurales (CEMES), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Christian Joachim, Advances in Atom and Single Molecule Machines, Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)

Subjects
[PHYS]Physics [physics]
Abstract

International audience; Imaging and Manipulation of Adsorbates using Dynamic Force Microscopy provides an overview of the latest developments in dynamic force microscopy (DFM) of atoms, molecules, and nanoparticles adsorbed on solid surfaces. Significant advances in the capabilities of this technique have been made in the last decade and this book represents a timely snapshot of the major research themes in the field, with a particular focus on the manipulation of matter at the atomic and (sub)molecular levels. This edited volume will be of keen interest to researchers active in nanoscience and its various sub-fields including, in particular, scanning probe microscopy. This book expands on the previous volumes in the series Advances in Atom and Single Molecule Machines. DFM is an exceptionally powerful tool for the imaging and probing of adsorbates on insulators and is now a component of the type of multiprobe interconnection systems described in Vol. 1 of the series. DFM can also be used to translate atoms and molecules in the context of the fabrication of the type of logic gates described in Vol. 2. When used in conjunction with STM, DFM also enables a detailed comparison of the chemical ‘architecture’ of a molecule with the spatial distribution of its orbital density, as described in Vol. 3. In this book readers will gain key insights into the current capabilities, and future potential, of dynamic force microscopy.

Published
2015
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32. Dynamic rayed aurora and enhanced ion-acoustic radar echoes

Author

Nickolay Ivchenko, B. S. Lanchester, E. M. Blixt, Tor Hagfors, T. Grydeland, T. S. Trondsen, C. La Hoz, U. P. Løvhaug, Dept. of Physics, University of Tromsø (UiT), School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Alfven Laboratory, Royal Institute of Technology [Stockholm] (KTH ), Max-Planck-Institut für Aeronomie (MPI Aeronomie), Max-Planck-Gesellschaft, Cornell University [New York], Institute for Space Research [Calgary], University of Calgary, and EGU, Publication

Subjects
Atmospheric Science, 010504 meteorology & atmospheric sciences, Field line, Population, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, ionosphere, Electron, Astrophysics, 01 natural sciences, law.invention, Ion, Low energy, law, plasma waves and instabilities, 0103 physical sciences, Earth and Planetary Sciences (miscellaneous), Radar, lcsh:Science, education, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Physics, education.field_of_study, [SDU.OCEAN] Sciences of the Universe [physics]/Ocean, Atmosphere, lcsh:QC801-809, Geology, Astronomy and Astrophysics, Geophysics, lcsh:QC1-999, Particle acceleration, lcsh:Geophysics. Cosmic physics, particle accelaration, Space and Planetary Science, VDP::Matematikk og Naturvitenskap: 400::Fysikk: 430::Rom- og plasmafysikk: 437, [SDU.STU] Sciences of the Universe [physics]/Earth Sciences, auroral ionosphere, lcsh:Q, Ionosphere, lcsh:Physics
Abstract

The generation mechanism for naturally enhanced ion-acoustic echoes is still debated. One important issue is how these enhancements are related to auroral activity. All events of enhanced ion-acoustic echoes observed simultaneously with the EISCAT Svalbard Radar (ESR) and with high-resolution narrow field-of-view auroral imagers have been collected and studied. Characteristic of all the events is the appearance of very dynamic rayed aurora, and some of the intrinsic features of these auroral displays are identified. Several of these identified features are directly related to the presence of low energy (10-100eV) precipitating electrons in addition to the higher energy population producing most of the associated light. The low energy contribution is vital for the formation of the enhanced ion-acoustic echoes. We argue that this type of aurora is sufficient for the generation of naturally enhanced ion-acoustic echoes. In one event two imagers were used to observe the auroral rays simultaneously, one from the radar site and one 7km away. The data from these imagers shows that the auroral rays and the strong backscattering filaments (where the enhanced echoes are produced) are located on the same field line, which is in contrast to earlier statements in the litterature that they should be separated.

Published
2005
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33. Suite of Hydrodynamical Simulations for the Lyman-Alpha Forest with Massive Neutrinos

Author

Nathalie Palanque-Delabrouille, Graziano Rossi, Arnaud Borde, James Rich, Jean-Marc Le Goff, Christophe Yèche, Matteo Viel, James S. Bolton, Sejong University, Département de Physique des Particules (ex SPP) (DPP), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Lawrence Berkeley National Laboratory [Berkeley] (LBNL), INAF - Osservatorio Astronomico di Trieste (OAT), Istituto Nazionale di Astrofisica (INAF), Istituto Nazionale di Fisica Nucleare (INFN), School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), We acknowledge PRACE for awarding us access to resource Curie-thin nodes based in France at TGCC, for our project 2012071264. This work was granted access to the HPC resources of CCRT under the allocation 2013-t2013047004 made by GENCI (Grand Equipement National de Calcul Intensif), ANR-11-JS04-0011,NuMass,Détermination de la masse des neutrinos cosmologiques(2011), European Project: 257670,EC:FP7:ERC,ERC-2010-StG_20091028,COSMOIGM(2010), and Département de Physique des Particules (ex SPP) (DPhP)

Subjects
Cold dark matter, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Large-scale structure of Universe, FOS: Physical sciences, Cosmology: observations, Cosmology: theory, Methods: numerical, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 7. Clean energy, 01 natural sciences, symbols.namesake, Settore FIS/05 - Astronomia e Astrofisica, 0103 physical sciences, Planck, 010303 astronomy & astrophysics, Physics, 010308 nuclear & particles physics, Equation of state (cosmology), Astronomy and Astrophysics, Quasar, Cosmology theory, Cosmology observations, Large-scale structure of Universe, Lyman-alpha forest, Baryon, Space and Planetary Science, Dark energy, symbols, Neutrino, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

The signature left in quasar spectra by the presence of neutral hydrogen in the Universe allows one to constrain the sum of the neutrino masses with improved sensitivity, with respect to laboratory experiments, and may shed a new light on the neutrino mass hierarchy and on the absolute mass scale of neutrinos. Constraints on cosmological parameters and on the dark energy equation of state can also be derived, from a joint parameter estimation procedure. However, this requires a detailed modeling of the line-of-sight power spectrum of the transmitted flux in the Lyman-Alpha (LyA) forest on scales ranging from a few to hundreds of Mpcs, which in turns demands the inclusion and careful treatment of cosmological neutrinos. To this end, we present here a suite of state-of-the-art hydrodynamical simulations with cold dark matter, baryons and massive neutrinos, specifically targeted for modeling the low-density regions of the IGM as probed by the LyA forest at high-redshift. The simulations span volumes ranging from (25 Mpc/h)^3 to (100 Mpc/h)^3, and are made using either 3 X 192^3~21 millions or 3 X 768^3~1.4 billion particles. The resolution of the various runs can be further enhanced, so that we can reach the equivalent of 3 X 3072^3~87 billion particles in a (100 Mpc/h)^3 box size. The chosen cosmological parameters are compatible with the latest Planck (2013) results, although we also explore the effect of slight variations in the main cosmological and astrophysical parameters. We adopt a particle-type implementation of massive neutrinos, and consider three degenerate species having masses M_nu =0.1, 0.2, 0.3, 0.4 and 0.8 eV, respectively. We improve on previous studies in several ways, in particular with updated routines for IGM radiative cooling and heating processes, and initial conditions based on 2LPT rather than the Zeldovich approximation., 22 pages, 14 figures, accepted for publication in A&A. Has a companion paper Borde et al. (2014)

Published
2014
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34. Cosmological Effects of Scalar-Photon Couplings: Dark Energy and Varying-alpha Models

Author

A. M. R. V. L. Monteiro, Carlos Martins, Anastasios Avgoustidis, G. Luzzi, P. E. Vielzeuf, School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Energie Noire, Laboratoire de l'Accélérateur Linéaire (LAL), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Particle physics, Cosmology and Nongalactic Astrophysics (astro-ph.CO), dark energy experiments, Ia, [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Cosmic microwave background, Scalar (mathematics), FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, 7. Clean energy, 01 natural sciences, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], 0103 physical sciences, 010303 astronomy & astrophysics, Luminosity distance, cosmology of theories beyond the SM, Physics, standard candles, baryon acoustic oscillations, 010308 nuclear & particles physics, Astronomy and Astrophysics, Redshift, Supernova, 13. Climate action, Dark energy, supernova type, Baryon acoustic oscillations, Scalar field, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

We study cosmological models involving scalar fields coupled to radiation and discuss their effect on the redshift evolution of the cosmic microwave background temperature, focusing on links with varying fundamental constants and dynamical dark energy. We quantify how allowing for the coupling of scalar fields to photons, and its important effect on luminosity distances, weakens current and future constraints on cosmological parameters. In particular, for evolving dark energy models, joint constraints on the dark energy equation of state combining BAO radial distance and SN luminosity distance determinations, will be strongly dominated by BAO. Thus, to fully exploit future SN data one must also independently constrain photon number non-conservation arising from the possible coupling of SN photons to the dark energy scalar field. We discuss how observational determinations of the background temperature at different redshifts can, in combination with distance measures data, set tight constraints on interactions between scalar fields and photons, thus breaking this degeneracy. We also discuss prospects for future improvements, particularly in the context of Euclid and the E-ELT and show that Euclid can, even on its own, provide useful dark energy constraints while allowing for photon number non-conservation., Comment: 29 pages, 11 figures; v2: Matches published version (JCAP)

Published
2014
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35. Modal 'self-coupling' as a sensitive probe for nanomechanical detection

Author

Christophe Blanc, Kunal Lulla, Eddy Collin, Andrew D. Armour, Martial Defoort, Olivier Bourgeois, Ultra-basses températures (UBT), Institut Néel (NEEL), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF), Thermodynamique et biophysique des petits systèmes (TPS), School of Physics and Astronomy [Nottingham], and University of Nottingham, UK (UON)

Subjects
Physics, Physics and Astronomy (miscellaneous), Condensed Matter - Mesoscale and Nanoscale Physics, business.industry, Local oscillator, Single-mode optical fiber, FOS: Physical sciences, Resonance, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Nonlinear system, Coupling (physics), Optics, Amplitude, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), 0103 physical sciences, Phase noise, 010306 general physics, 0210 nano-technology, business, [PHYS.COND.CM-MSQHE]Physics [physics]/Condensed Matter [cond-mat]/Mesoscopic Systems and Quantum Hall Effect [cond-mat.mes-hall], Free parameter
Abstract

International audience; We present a high-sensitivity measurement technique for mechanical nanoresonators. Due to intrinsic nonlinear effects, different flexural modes of a nanobeam can be coupled while driving each of them on resonance. This mode-coupling scheme is dispersive and one mode resonance shifts with respect to the motional amplitude of the other. The same idea can be implemented on a single mode, exciting it with two slightly detuned signals. This two-tone scheme is used here to measure the resonance lineshape of one mode through a frequency shift in the response of the device. The method acts as an amplitude-to-frequency transduction which ultimately suffers only from phase noise of the local oscillator used and of the nanomechanical device itself. We also present a theory which reproduces the data without free parameters

Published
2013
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36. Storing magnetic information in IrMn/MgO/Ta tunnel junctions via field-cooling

Author

Petti, D., Albisetti, E., Reichlová, H., Gázquez Alabart, Jaume, Varela, M., Molina Ruiz, Manel, Lopeandía Fernández, Aitor, Olejník, K., Novák, V., Fina, Ignasi, Dkhil, B., Hayakawa, J., Marti, X., Wunderlich, J., Jungwirth, T., Bertacco, Riccardo, American Institute of Physics, Politecn Milan, LNESS Dipartimento Fis, I-22100 Como, Italy, Institute of Physics ASCR, Institute of Physics of the Czech Academy of Sciences (FZU), Charles University, Faculty of Mathematics and Physics, Czech Republic, Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Oak Ridge National Laboratory [Oak Ridge] (ORNL), UT-Battelle, LLC, Departament de Fisica, Universitat Autonoma de Barcelona, Universitat Autònoma de Barcelona [Barcelona] (UAB), Laboratoire Structures, Propriétés et Modélisation des solides (SPMS), CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Hitachi Ltd., Advanced Research Laboratory, Departement of Physics, University of California, Universite de Californie, Hitachi Cambridge Laboratory, School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Institute of Physics of the Czech Academy of Sciences (FZU / CAS), Czech Academy of Sciences [Prague] (CAS)-Czech Academy of Sciences [Prague] (CAS), Faculty of Mathematics and Physics [Charles University of Praha], Charles University [Prague] (CU), Universitat Autònoma de Barcelona (UAB), Institut de Chimie du CNRS (INC)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Hitachi, Ltd, Hitachi Cambridge Laboratory [University of Cambridge], and University of Cambridge [UK] (CAM)-Hitachi, Ltd

Subjects
Materials science, Physics and Astronomy (miscellaneous), Tunneling, Tantalum, chemistry.chemical_element, FOS: Physical sciences, 02 engineering and technology, 01 natural sciences, Atomic force microscopy, Magnetic tunnel junctions, [SPI]Engineering Sciences [physics], Antiferromagnetism, Metastability, 0103 physical sciences, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), 010306 general physics, Antiferromagnet spintronics, Quantum tunnelling, ComputingMilieux_MISCELLANEOUS, Condensed Matter - Materials Science, Condensed matter physics, Condensed Matter - Mesoscale and Nanoscale Physics, Materials Science (cond-mat.mtrl-sci), 021001 nanoscience & nanotechnology, Magnetic field, Active layer, chemistry, Ferromagnetism, Magnetic fields, 0210 nano-technology, Néel temperature
Abstract

International audience; Tunneling junctions containing no ferromagnetic elements have been fabricated and we show that distinct resistance states can be set by field cooling the devices from above the Néel along different orientations. Variations of the resistance up to 10% are found upon field cooling in applied fields of 2T, in-plane or out of plane. Below T N , we found that the metastable states are insensitive to magnetic fields thus constituting a memory element robust against external magnetic fields. Our work provides the demonstration of an electrically readable magnetic memory device, which contains no ferromagnetic elements and stores the information in an antiferromagnetic active layer.

Published
2013
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37. Deep-level transient spectroscopy of interfacial states in 'buffer-free' p-i-n GaSb/GaAs devices

Author

Jorlandio F. Felix, Mohsin Aziz, Azzouz Sellai, Mohamed Henini, Noor Al Saqri, Dler Jameel, Abdelmadjid Mesli, R. H. Mari, A. Khatab, D. Taylor, Philippe Ferrandis, School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Université de Toulon (UTLN), Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information (CEA-LETI), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut des Matériaux, de Microélectronique et des Nanosciences de Provence (IM2NP), Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), Universidade Federal de Viçosa = Federal University of Viçosa (UFV), Sultan Qaboos University (SQU), Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), and Universidade Federal de Vicosa (UFV)

Subjects
010302 applied physics, Deep-level transient spectroscopy, Materials science, Condensed matter physics, Passivation, Band gap, General Physics and Astronomy, 02 engineering and technology, Electronic density of states, Semiconductor device, 021001 nanoscience & nanotechnology, 01 natural sciences, Gallium arsenide, chemistry.chemical_compound, chemistry, 0103 physical sciences, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Atomic physics, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, 0210 nano-technology
Abstract

International audience; A systematic study was carried out on defect states in Interfacial Misfit (IMF) unpassivated and Te-passivated IMF in p-i-n GaSb/GaAs devices using Deep Level Transient Spectroscopy (DLTS) and Laplace DLTS. Additionally, Current-Voltage (I–V) measurements were performed, which showed that the turn-on voltage (Von) of passivated samples is lower than that for unpassivated samples; an effect which can be explained by the introduction of new defects states near to the interface of GaSb/GaAs, where Te was incorporated to passivate the IMF. The Capacitance-Voltage (C-V) analysis demonstrates that these new states are the consequence of adding Te at the misfit of GaSb/GaAs. Furthermore, DLTS measurements reveal a distribution of states including a main midgap energy level, namely the well documented EL2 trap, with some peculiar behaviour. Most of these levels are related to interface states that are generated by the mismatch between GaAs and GaSb. Originally, the addition of Te atoms was thought to passivate these interface states. On the contrary, this paper, which attempts at correlating the current-voltage and capacitance-voltage characteristics to the DLTS results, shows clearly that Te atoms increase the density of interface states.

Published
2013
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38. Herschel observations of a z similar to 2 stellar mass selected galaxy sample drawn from the GOODS NICMOS Survey

Author

Hilton, M., Conselice, C. J., Roseboom, I. G., Burgarella, D., Buat, V., Berta, S., Béthermin, M., Bock, J., Chapman, S. C., Clements, D. L., Conley, A., Conversi, L., Cooray, A., Farrah, D., Ibar, E., Magdis, G., Magnelli, B., Marsden, G., Nordon, R., Oliver, S. J., Page, M. J., Popesso, P., Pozzi, F., Schulz, B., Scott, Douglas, Smith, A. J., Symeonidis, M., Valtchanov, I., Viero, M., Wang, L., Zemcov, M., School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Astronomy Centre, University of Sussex, 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), Max-Planck-Institut für Extraterrestrische Physik (MPE), 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), CHANG (CHANG), Laboratoire d'étude des transferts en hydrologie et environnement (LTHE), 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 National Polytechnique de Grenoble (INPG)-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 National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS), Centre for Fusion Space and Astrophysics [Coventry] (CFSA), University of Warwick [Coventry], National Center for Atmospheric Research [Boulder] (NCAR), Herschel Science Center [Madrid], European Space Astronomy Centre (ESAC), Agence Spatiale Européenne = European Space Agency (ESA)-Agence Spatiale Européenne = European Space Agency (ESA), California Institute of Technology (CALTECH), UK Astronomy Technology Centre (UK ATC), Science and Technology Facilities Council (STFC), 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)-Centre National d’Études Spatiales [Paris] (CNES), Department of Physics and Astronomy [Vancouver], University of British Columbia (UBC), Department of Chemistry and Biochemistry, University of California [Los Angeles] (UCLA), University of California (UC)-University of California (UC), Dipartimento di Astronomia, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Computing and Mathematical Sciences [Pasadena]], British Antarctic Survey (BAS), Natural Environment Research Council (NERC), Space Science & Technology Department, Rutheford Appleton Laboratory, Herschel Science Centre, Agence Spatiale Européenne = European Space Agency (ESA), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Jean Monnet - Saint-Étienne (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), 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), European Space Agency (ESA)-European Space Agency (ESA), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), University of California-University of California, European Space Agency (ESA), Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), CHANG, Laboratoire de glaciologie et géophysique de l'environnement (LGGE), 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)-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)-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)-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), Università di Bologna [Bologna] (UNIBO), Institut National Polytechnique de Grenoble (INPG)-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), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO), [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], FOS: Physical sciences, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

We present a study of the far-IR properties of a stellar mass selected sample of 1.5 < z < 3 galaxies with log(M_*/M_sun) > 9.5 drawn from the GOODS NICMOS Survey (GNS), the deepest H-band Hubble Space Telescope survey of its type prior to the installation of WFC3. We use far-IR and sub-mm data from the PACS and SPIRE instruments on-board Herschel, taken from the PACS Evolutionary Probe (PEP) and Herschel Multi-Tiered Extragalactic Survey (HerMES) key projects respectively. We find a total of 22 GNS galaxies, with median log(M_*/M_sun) = 10.8 and z = 2.0, associated with 250 um sources detected with SNR > 3. We derive mean total IR luminosity log L_IR (L_sun) = 12.36 +/- 0.05 and corresponding star formation rate SFR_(IR+UV) = (280 +/- 40) M_sun/yr for these objects, and find them to have mean dust temperature T_dust ~ 35 K. We find that the SFR derived from the far-IR photometry combined with UV-based estimates of unobscured SFR for these galaxies is on average more than a factor of 2 higher than the SFR derived from extinction corrected UV emission alone, although we note that the IR-based estimate is subject to substantial Malmquist bias. To mitigate the effect of this bias and extend our study to fainter fluxes, we perform a stacking analysis to measure the mean SFR in bins of stellar mass. We obtain detections at the 2-4 sigma level at SPIRE wavelengths for samples with log(M_*/M_sun) > 10. In contrast to the Herschel detected GNS galaxies, we find that estimates of SFR_(IR+UV) for the stacked samples are comparable to those derived from extinction corrected UV emission, although the uncertainties are large. We find evidence for an increasing fraction of dust obscured star formation with stellar mass, finding SFR_IR/SFR_UV \propto M_*^{0.7 +/- 0.2}, which is likely a consequence of the mass--metallicity relation., Accepted for publication in MNRAS, 17 pages, 17 figures; added/updated references

Published
2012
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39. Quantum current noise from a Born-Markov master equation

Author

Fabio Pistolesi, Andrew D. Armour, Peter Kirton, Manuel Houzet, School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Service de Physique Statistique, Magnétisme et Supraconductivité (SPSMS - UMR 9001), Institut Nanosciences et Cryogénie (INAC), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire Ondes et Matière d'Aquitaine (LOMA), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS), EPSRC (U.K.) - EP/I017828/1, ANR-11-JS04-0003,GLASNOST,Lois générales pour la supraconductivité mésoscopique en régime hors d'équilibre non-stationnaire(2011), ANR-10-BLAN-0404,QNM,Nano Mécanique Quantique(2010), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])

Subjects
FOS: Physical sciences, PACS: 72.70.+m, 42.50.Lc, 85.25.-j, 01 natural sciences, Noise (electronics), Electric charge, Noise processes and phenomena, 010305 fluids & plasmas, [PHYS.QPHY]Physics [physics]/Quantum Physics [quant-ph], Quantum mechanics, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), 0103 physical sciences, Master equation, Quantum fluctuations - quantum noise and quantum jumps, 010306 general physics, Quantum, QC, Physics, Mesoscopic physics, Quantum Physics, Condensed Matter - Mesoscale and Nanoscale Physics, Quantum noise, Shot noise, Condensed Matter Physics, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Electronic, Optical and Magnetic Materials, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Superconducting devices, Quasiparticle, Quantum Physics (quant-ph)
Abstract

We present a formalism for calculating the non-symmetrized quantum current noise within the Born-Markov approximation for the master equation. The formalism is particularly well suited to obtaining the current noise for quantum transport in mesoscopic devices such as a superconducting single electron transistor (SSET). As an example of the method, we obtain explicit results for the double Josephson-quasiparticle (DJQP) resonance in a SSET. Our calculations reveal the asymmetries that develop in the current noise as well as clarifying the behavior at high frequencies. Our findings are consistent with recent measurements of the asymmetry in the current noise spectrum., 5 pages, 3 figures

Published
2012
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40. General second order scalar-tensor theory, and the fab 4

Author

Charmousis, Christos, Copeland, E.J., Padilla, Antonio, Saffin, Paul M., Starita, Sabine, Laboratoire de Physique Théorique d'Orsay [Orsay] (LPT), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Laboratoire de Mathématiques et Physique Théorique (LMPT), Université de Tours-Centre National de la Recherche Scientifique (CNRS), School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), and Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.GRQC] Physics [physics]/General Relativity and Quantum Cosmology [gr-qc], [PHYS.GRQC]Physics [physics]/General Relativity and Quantum Cosmology [gr-qc], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2012

41. Inactive dynamical phase of a symmetric exclusion process on a ring

Author

Frédéric van Wijland, Juan P. Garrahan, Vivien Lecomte, Laboratoire de Probabilités et Modèles Aléatoires (LPMA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Matière et Systèmes Complexes (MSC (UMR_7057)), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Matière et Systèmes Complexes (MSC), and Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)

Subjects
Statistics and Probability, FOS: Physical sciences, General Physics and Astronomy, Ring (chemistry), 01 natural sciences, Molecular physics, large deviations, 010305 fluids & plasmas, Simple (abstract algebra), [MATH.MATH-ST]Mathematics [math]/Statistics [math.ST], Phase (matter), 0103 physical sciences, exclusion process, [PHYS.COND.CM-SM]Physics [physics]/Condensed Matter [cond-mat]/Statistical Mechanics [cond-mat.stat-mech], 010306 general physics, Condensed Matter - Statistical Mechanics, rare fluctuations, Mathematical Physics, Physics, Range (particle radiation), Statistical Mechanics (cond-mat.stat-mech), Single cluster, Process (computing), Statistical and Nonlinear Physics, [STAT.TH]Statistics [stat]/Statistics Theory [stat.TH], Inactive phase, Modeling and Simulation
Abstract

http://iopscience.iop.org/1751-8121/45/17/175001; International audience; We investigate the nature of the dynamically inactive phase of a simple symmetric exclusion process on a ring. We find that as the system's activity is tuned to a lower-than-average value the particles progressively lump into a single cluster, thereby forming a kink in the density profile. All dynamical regimes, and their finite size range of validity, are explicitly determined.

Published
2012
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42. Increase of the chemical potential and phase transitions in four-component exciton condensates subject to magnetic fields

Author

Yuri G. Rubo, Alexey Kavokin, Centro de Investigación en Energía, Universidad Nacional Autónoma de México (UNAM), Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), School of Physics and Astronomy [Nottingham], and University of Nottingham, UK (UON)

Subjects
Physics, Condensed Matter::Quantum Gases, Phase transition, Condensed matter physics, [PHYS.COND.GAS]Physics [physics]/Condensed Matter [cond-mat]/Quantum Gases [cond-mat.quant-gas], Condensed Matter::Other, Exciton, PACS: 78.67.De, 42.55.Sa, 71.36.+c, 78.20.Ls, Degenerate energy levels, 02 engineering and technology, Spin structure, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, 7. Clean energy, Electronic, Optical and Magnetic Materials, Magnetic field, 0103 physical sciences, 010306 general physics, 0210 nano-technology, Ground state, Biexciton, Spin-½
Abstract

We analyze the spin structure of the ground state of four-component exciton condensates in coupled quantum wells as a function of spin-dependent interactions and applied magnetic field. The four components correspond to the degenerate exciton states characterized by $\ifmmode\pm\else\textpm\fi{}2$ and $\ifmmode\pm\else\textpm\fi{}1$ spin projections to the axis of the structure. We show that in a wide range of parameters, the chemical potential of the system increases as a function of magnetic field, which manifests a pseudo-diamagnetism of the system. The transitions to polarized two- and one-component condensates can be of the first-order in this case. The predicted effects are caused by energy-conserving mixing of $\ifmmode\pm\else\textpm\fi{}2$ and $\ifmmode\pm\else\textpm\fi{}1$ excitons.

Published
2011
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43. Terahertz Detection of Quantum Cascade Laser Emission by Plasma Waves in Field Effect Transistors

Author

B. Chenaud, Saeed Fathololoumi, Christophe Chaubet, A. El Fatimy, Dominique Coquillat, Christophe Consejo, P. Buzatu, Wojciech Knap, M. S. Zholudev, Frederic Teppe, Nina Dyakonova, Z. R. Wasilewski, Jérémi Torres, Pierre Solignac, Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institut d’Electronique et des Systèmes (IES), Térahertz, hyperfréquence et optique (TéHO), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institute for Microstructural Sciences (NRC - IMS), National Research Council of Canada (NRC), Institute for Physics of Microstructures of the RAS, Russian Academy of Sciences [Moscow] (RAS), School of Physics and Astronomy [Nottingham], and University of Nottingham, UK (UON)

Subjects
Physical mechanism, Solid state lasers, Terahertz radiation, Quantum cascade lasers, General Physics and Astronomy, 02 engineering and technology, 01 natural sciences, law.invention, Photomixing, Computer Science::Hardware Architecture, Computer Science::Emerging Technologies, law, Terahertz detection, Drain current, 010302 applied physics, Physics, Waves in plasmas, Transistor, Detectors, Quantum cascades, Liquid nitrogen, 021001 nanoscience & nanotechnology, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Terahertz systems, All-solid-state, Plasma waves, Cascade, Optoelectronics, plasma oscillations, Field-effect transistor, 0210 nano-technology, Quantum cascade laser, Transistor channels, Saturation regime, PACS: 85.30.Tv, 07.57.Kp, 52.35.-g, Transistors, GaAs/AlGaAs, 0103 physical sciences, Terahertz wave detectors, Liquid nitrogen temperature, [PHYS.COND.CM-MSQHE]Physics [physics]/Condensed Matter [cond-mat]/Mesoscopic Systems and Quantum Hall Effect [cond-mat.mes-hall], business.industry, Nitrogen plasma, Terahertz waves, Laser, THz radiation, Gate length, Quantum theory, Resonant detection, Nanometer size, Gates (transistor), business
Abstract

International audience; We report on the resonant detection of a 3.1 THz radiation produced by a quantum cascade laser using a 250 nm gate length GaAs/AlGaAs field effect transistor at liquid nitrogen temperature. We show that the physical mechanism of the detection is related to the plasma waves excited in the transistor channel. The detection is enhanced by increasing the drain current and driving the transistor into saturation regime. These results clearly show that plasma wave nanometer-size transistors can be used as detectors in all-solid-state terahertz systems where quantum cascade lasers act as sources.

Published
2011
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44. Charge noise at Cooper-pair resonances

Author

Fabio Pistolesi, Andrew D. Armour, Manuel Houzet, Peter Kirton, School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Institut Nanosciences et Cryogénie (INAC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Laboratoire de physique et modélisation des milieux condensés (LPM2C), Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Centre de physique moléculaire optique et hertzienne (CPMOH), Université Sciences et Technologies - Bordeaux 1 (UB)-Centre National de la Recherche Scientifique (CNRS), ANR-06-JCJC-0036,NEMESIS,NanoElectroMEchanical transport and Shuttling In normal and superconducting Systems(2006), and Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1

Subjects
Charge qubit, TK, FOS: Physical sciences, Noise spectrum, 02 engineering and technology, 01 natural sciences, law.invention, symbols.namesake, law, Quantum mechanics, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), 0103 physical sciences, Master equation, dissipative systems, Zero frequency, 010306 general physics, QC, [PHYS.COND.CM-MSQHE]Physics [physics]/Condensed Matter [cond-mat]/Mesoscopic Systems and Quantum Hall Effect [cond-mat.mes-hall], Superconductivity, Physics, Condensed Matter - Mesoscale and Nanoscale Physics, superconducting single electron transistor, Transistor, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Electronic, Optical and Magnetic Materials, symbols, Cooper pair, Atomic physics, 0210 nano-technology, Hamiltonian (quantum mechanics)
Abstract

We analyze the charge dynamics of a superconducting single-electron transistor (SSET) in the regime where charge transport occurs via Cooper-pair resonances. Using an approximate description of the system Hamiltonian, in terms of a series of resonant doublets, we derive a Born-Markov master equation describing the dynamics of the SSET. The average current displays sharp peaks at the Cooper-pair resonances and we find that the charge noise spectrum has a characteristic structure which consists of a series of asymmetric triplets of peaks. The strongest feature in the charge noise spectrum is the triplet of peaks centered at zero frequency which has a peak spacing equal to the level separation within the doublets and is similar to the triplet in the spectrum of a driven, damped, two-level system. We also explore the back-action that the SSET charge noise would have on an oscillator coupled to the island charge, measurement of which provides a way of probing the charge noise spectrum., 14 pages, 7 figures

Published
2010
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45. Dressing of ultracold atoms by their Rydberg states in a IoffePritchard trap

Author

Igor Lesanovsky, Michael Mayle, Peter Schmelcher, Zentrum für Optische Quantentechnologien | Center for Optical Quantum Technologies [Hamburg] (ZOQ), Universität Hamburg (UHH), School of Physics and Astronomy [Nottingham], and University of Nottingham, UK (UON)

Subjects
Atomic Physics (physics.atom-ph), FOS: Physical sciences, Trapping, 01 natural sciences, Physics - Atomic Physics, 010305 fluids & plasmas, law.invention, symbols.namesake, Quantization (physics), Ultracold atom, law, 0103 physical sciences, Physics::Atomic Physics, 010306 general physics, 32.80.Ee, 32.60.+i, Physics, Condensed Matter::Quantum Gases, 37.10.Gh, 32.10.Ee, 16. Peace & justice, Condensed Matter Physics, Laser, Atomic and Molecular Physics, and Optics, Rydberg atom, Rydberg formula, symbols, Atomic physics, Ground state
Abstract

We explore how the extraordinary properties of Rydberg atoms can be employed to impact the motion of ultracold ground state atoms. Specifically, we use an off-resonant two-photon laser dressing to map features of the Rydberg states on ground state atoms. It is demonstrated that the interplay between the spatially varying quantization axis of the considered Ioffe-Pritchard field and the fixed polarizations of the laser transitions provides the possibility of substantially manipulating the ground state trapping potential., 11 pages, 4 figures

Published
2010
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46. Academic Software Toolboxes for the Analysis of MEG Data

Author

Baillet, Sylvain, Leahy, Richard, Tadel, François, Mosher, John, Delorme, Arnaud, Makeig, Scott, Oostenveld, Robert, Hämäläinen, Matti, Dalal, Sarang, Zumer, J., Clerc, Maureen, Wolters, Carsten, Kiebel, Stefan, Jensen, Ole, Department of Neurology [Milwaukee], Medical College of Wisconsin, University of South California (USC), Neuroimaging group, Cleveland Clinic, Centre de recherche cerveau et cognition (CERCO), Institut des sciences du cerveau de Toulouse. (ISCT), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Swartz Center for Computational Neuroscience, University of California [San Diego] (UC San Diego), University of California-University of California, Donders Institute for Brain, Cognition and Behaviour, Radboud university [Nijmegen], Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital [Boston]-Harvard Medical School [Boston] (HMS), Dynamique Cérébrale et Cognition, Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de la Santé et de la Recherche Médicale (INSERM), School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Computational Imaging of the Central Nervous System (ATHENA), Inria Sophia Antipolis - Méditerranée (CRISAM), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Institute for Biomagnetism and Biosignal Analysis, Westfälische Wilhelms-Universität Münster (WWU), Max Planck Institute for Human Cognitive and Brain Sciences [Leipzig] (IMPNSC), Max-Planck-Gesellschaft, S. Supek, Supek, Selma and Susac, Ana, University of Southern California (USC), Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre Hospitalier Universitaire de Toulouse (CHU Toulouse)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Centre Hospitalier Universitaire de Toulouse (CHU Toulouse)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), University of California (UC)-University of California (UC), Radboud University [Nijmegen], Harvard Medical School [Boston] (HMS)-Massachusetts General Hospital [Boston], Westfälische Wilhelms-Universität Münster = University of Münster (WWU), Clerc, Maureen, and Supek, Selma and Susac, Ana

Subjects
MEG, [SCCO.COMP] Cognitive science/Computer science, connectivity, data analysis, imaging, [SCCO.COMP]Cognitive science/Computer science, source analysis, mapping, forward modeling
Abstract

International audience; Free MEG and EEG data analysis software packages springing from academic research are now widely used in published work. These toolboxes and applications are typically developed by or in close contact with researchers addressing cognitive or clinical neuroscience questions. Thus they often contain the latest methodological developments from the research community. It is therefore vital to educate MEG researchers and make them aware of the new possibilities offered by these toolboxes. The aim of this paper is to illustrate the characteristics and advantages of the various toolboxes to users and developers alike. We present each toolbox with their key features and target audience.

Published
2010

47. NMR structure of rALF-Pm3, an anti-lipopolysaccharide factor from shrimp: Model of the possible lipid A-binding site

Author

Delphine Destoumieux-Garzón, Hélène Boze, André Padilla, Yinshan Yang, André Aumelas, Yannick Gueguen, Françoise Roquet, Patrick Chemardin, Martine Pugnière, Evelyne Bachère, Guy Moulin, Anchalee Tassanakajon, Ningxia Medical College, Algorithms and Scheduling for Distributed Heterogeneous Platforms (GRAAL), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire de l'Informatique du Parallélisme (LIP), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Beijing Institute of Technology (BIT), Centre de Biochimie Structurale [Montpellier] (CBS), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), CSIR National Institute of Oceanography [India] (NIO), Institut de Recherche en Infectiologie de Montpellier (IRIM), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Ecosystèmes lagunaires : organisation biologique et fonctionnement (ECOLAG), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de chimie et biochimie des substances naturelles, Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Genome Population & Interactions, Université Montpellier 2 - Sciences et Techniques (UM2)-ORSTOM-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de la Santé et de la Recherche Médicale (INSERM), Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN), and PADILLA, André

Subjects
Models, Molecular, LIPID A, STRUCTURE, [SDV.BIO]Life Sciences [q-bio]/Biotechnology, Invertebrate Hormones, LIPOPOLYSACCHARIDE, Crystallography, X-Ray, Biochemistry, Penaeus monodon, Lipid A, Crustacea, Septic shock, SURFACE PLASMON RESONANCE ULTRACENTRIFUGATION, Surface plasmon resonance, [INFO.INFO-BT]Computer Science [cs]/Biotechnology, ANTI-LIPOPOLYSACCHARIDE FACTOR, Tachypleus tridentatus, 0303 health sciences, Anti lipopolysaccharide factor, biology, Chemistry, 030302 biochemistry & molecular biology, digestive, oral, and skin physiology, General Medicine, Ultracentrifuge, Protein Binding, Molecular Sequence Data, Biophysics, Lipopolysaccharide, Pichia pastoris, Biomaterials, 03 medical and health sciences, Animals, Amino Acid Sequence, Binding site, Nuclear Magnetic Resonance, Biomolecular, 030304 developmental biology, Binding Sites, Organic Chemistry, SEPTIC SHOCK, Structure, Surface Plasmon Resonance, biology.organism_classification, NMR, Protein Structure, Tertiary, [SDV.BIO] Life Sciences [q-bio]/Biotechnology, [INFO.INFO-BT] Computer Science [cs]/Biotechnology, POLYSACCHARIDE, Structural Homology, Protein, Limulus, Sequence Alignment, Ultracentrifugation
Abstract

Correspondance auteur: Aumelas A. E-mail: aumelas@cbs.cnrs.fr; International audience; The anti-lipopolysaccharide factor ALF-Pm3 is a 98-residue protein identified in hemocytes from the black tiger shrimp Penaeus monodon. It was expressed in Pichia pastoris from the constitutive glyceraldehyde-3-phosphate dehydrogenase promoter as a folded and N-15 uniformly labeled rALF-Pm3 protein. Its 3D structure was established by NMR and consists of three alpha-helices packed against a four-stranded beta-sheet. The C-34-C-55 disulfide bond was shown to be essential for the structure stability. By using surface plasmon resonance, we demonstrated that rALF-Pm3 binds to LPS, lipid A and to OM(R)-174, a soluble analogue of lipid A. Biophysical studies of rALF-Pm3/LPS and rALF-Pm3/OM(R)-174 complexes indicated rather high molecular sized aggregates, which prevented us to experimentally determine by NMR the binding mode of these lipids to rALF-Pm3. However, on the basis of striking structural similarities to the FhuA/LPS complex, we designed an original model of the possible lipid A-binding site of ALF-Pm3. Such a binding site, located on the ALF-Pm3 beta-sheet and involving seven charged residues, is well conserved in ALF-L from Limulus polyphemus and in ALF-T from Tachypleus tridentatus. In addition, our model is in agreement with experiments showing that beta-hairpin synthetic peptides corresponding to ALF-L beta-sheet bind to LPS. Delineating lipid A-binding site of ALFs will help go further in the de novo design of new antibacterial or LPS-neutralizing drugs

Published
2009
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48. First-order dynamical phase transition in models of glasses: an approach based on ensembles of histories

Author

Vivien Lecomte, Robert L. Jack, Estelle Pitard, Juan P. Garrahan, K. van Duijvendijk, F. van Wijland, School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Department of Chemistry [Berkeley], University of California [Berkeley], University of California-University of California, Matière et Systèmes Complexes (MSC (UMR_7057)), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des colloïdes, verres et nanomatériaux (LCVN), Université Montpellier 2 - Sciences et Techniques (UM2)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)

Subjects
Statistics and Probability, Physics, Phase transition, Statistical Mechanics (cond-mat.stat-mech), FOS: Physical sciences, General Physics and Astronomy, Statistical and Nonlinear Physics, First order, 01 natural sciences, PACS numbers: 05.40.?a, 64.70.Pf, 010305 fluids & plasmas, Modeling and Simulation, Lattice (order), 0103 physical sciences, Statistical physics, [PHYS.COND.CM-SM]Physics [physics]/Condensed Matter [cond-mat]/Statistical Mechanics [cond-mat.stat-mech], 010306 general physics, Condensed Matter - Statistical Mechanics, Mathematical Physics, Deviation function
Abstract

We investigate the dynamics of kinetically constrained models of glass formers by analysing the statistics of trajectories of the dynamics, or histories, using large deviation function methods. We show that, in general, these models exhibit a first-order dynamical transition between active and inactive dynamical phases. We argue that the dynamical heterogeneities displayed by these systems are a manifestation of dynamical first-order phase coexistence. In particular, we calculate dynamical large deviation functions, both analytically and numerically, for the Fredrickson-Andersen model, the East model, and constrained lattice gas models. We also show how large deviation functions can be obtained from a Landau-like theory for dynamical fluctuations. We discuss possibilities for similar dynamical phase-coexistence behaviour in other systems with heterogeneous dynamics., 29 pages, 7 figs, final version

Published
2009
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49. Strong coupling in Horava gravity

Author

Antonio Padilla, Gustavo Niz, Christos Charmousis, Paul M. Saffin, Starita, Sabine, Laboratoire de Physique Théorique d'Orsay [Orsay] (LPT), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Laboratoire de Mathématiques et Physique Théorique (LMPT), Université de Tours-Centre National de la Recherche Scientifique (CNRS), School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), and Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, High Energy Physics - Theory, Nuclear and High Energy Physics, [PHYS.GRQC] Physics [physics]/General Relativity and Quantum Cosmology [gr-qc], 010308 nuclear & particles physics, Gravitational wave, General relativity, [PHYS.HTHE]Physics [physics]/High Energy Physics - Theory [hep-th], Degrees of freedom (physics and chemistry), FOS: Physical sciences, Detailed balance, General Relativity and Quantum Cosmology (gr-qc), Symmetry group, Fixed point, 01 natural sciences, General Relativity and Quantum Cosmology, Theoretical physics, High Energy Physics - Theory (hep-th), 0103 physical sciences, [PHYS.GRQC]Physics [physics]/General Relativity and Quantum Cosmology [gr-qc], [PHYS.HTHE] Physics [physics]/High Energy Physics - Theory [hep-th], Diffeomorphism, 010306 general physics, Scaling
Abstract

By studying perturbations about the vacuum, we show that Horava gravity suffers from two different strong coupling problems, extending all the way into the deep infra-red. The first of these is associated with the principle of detailed balance and explains why solutions to General Relativity are typically not recovered in models that preserve this structure. The second of these occurs even without detailed balance and is associated with the breaking of diffeomorphism invariance, required for anisotropic scaling in the UV. Since there is a reduced symmetry group there are additional degrees of freedom, which need not decouple in the infra-red. Indeed, we use the Stuckelberg trick to show that one of these extra modes become strongly coupled as the parameters approach their desired infra-red fixed point. Whilst we can evade the first strong coupling problem by breaking detailed balance, we cannot avoid the second, whatever the form of the potential. Therefore the original Horava model, and its "phenomenologically viable" extensions do not have a perturbative General Relativity limit at any scale. Experiments which confirm the perturbative gravitational wave prediction of General Relativity, such as the cumulative shift of the periastron time of binary pulsars, will presumably rule out the theory., Comment: 11 pages

Published
2009

50. Superfluid pairing between fermions with unequal masses

Author

Mikhail A. Baranov, Carlos Lobo, G. V. Shlyapnikov, Van der Waals-Zeeman Institute, Institut für Quantenoptik und Quanteninformation, National Research Center 'Kurchatov Institute' (NRC KI), School of Physics and Astronomy [Nottingham], University of Nottingham, UK (UON), Laboratoire de Physique Théorique et Modèles Statistiques (LPTMS), and Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)

Subjects
Condensed Matter::Quantum Gases, Physics, Scattering, Condensed Matter - Superconductivity, FOS: Physical sciences, Scattering length, Fermion, Mass ratio, 01 natural sciences, Atomic and Molecular Physics, and Optics, 010305 fluids & plasmas, Condensed Matter - Other Condensed Matter, Superconductivity (cond-mat.supr-con), [PHYS.COND.CM-S]Physics [physics]/Condensed Matter [cond-mat]/Superconductivity [cond-mat.supr-con], Superfluidity, Momentum, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Quantum electrodynamics, Pairing, Quantum mechanics, 0103 physical sciences, Perturbation theory, 010306 general physics, Other Condensed Matter (cond-mat.other)
Abstract

We consider a superfluid state in a two-component gas of fermionic atoms with equal densities and unequal masses in the BCS limit. We develop a perturbation theory along the lines proposed by Gorkov and Melik-Barkhudarov and find that for a large difference in the masses of heavy ($M$) and light ($m$) atoms one has to take into account both the second-order and third-order contributions. The result for the critical temperature and order parameter is then quite different from the prediction of the simple BCS approach. Moreover, the small parameter of the theory turns out to be $(p_{F}|a|)/\hbar)\sqrt{M/m}\ll1$, where $p_{F}$ is the Fermi momentum, and $a$ the scattering length. Thus, for a large mass ratio $M/m$ the conventional perturbation theory requires significantly smaller Fermi momenta (densities) or scattering lengths than in the case of $M\sim m$, where the small parameter is $(p_{F}|a|)/\hbar)\ll1$. We show that 3-body scattering resonances appearing at a large mass ratio due to the presence of 3-body bound Efimov states do not influence the result, which in this sense becomes universal., Comment: 21 pages, 9 figures, 1 table, discussions added

Published
2008
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