Author: "Alain Delboulbé" - Searchworks@Jio Institute Digital Library Search Results

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1. First evidence of polarized emissions in pulsating aurorae

Author: Leo Bosse, Gaël Cessateur, Hervé Lamy, Jean Lilensten, Nicolas Gillet, Colette Brogniez, Olivier Pujol, Sylvain Rochat, Stéphane Curaba, Alain Delboulbé, and Magnar G. Johnsen
Abstract: In the last decade, several instruments have been developped to measure the auroral light polarisation. However, its study has faced the issue of anthropic light pollution and scattering in the lower atmosphere (Bosse et al., 2020). To overcome this challenge, several methods were used, and until now, the most succesfull was the use of a polarised radiative transfer model (Bosse et al., 2022) to identify the light pollution contribution. However during the past year a new look at the data revealed that pulsating aurorae are polarised, and that this polarisation carries a lot of information. The main advantage of using pulsating aurorae is that the variations in the light polarisation are very fast, of the order of a few seconds. This allows us to dismiss any potential source of polarisation that are not synched with the pulsation of the aurora.These polarisation patterns are seen in the green atomic oxygen line at 557.7 nm, the 1st N2+ negative band at 391.4 nm (purple) and 427.8 nm (blue).There are no clear explanations on the origin of this auroral polarisation, or its relation to the local state of the upper atmosphere. An hypothesis is that this polarisation can be either created directly at the radiative de-excitation or may occur when the non-polarised emission crosses the ionospheric currents.We will present how these new findings confirm the ionospheric origin of the polarisation observed from the ground, as well as some of the potentialities these observations and models offer in the frame of space weather, aerosol and light pollution study.
Published: 2023
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2. Impact of local turbulence on high-order adaptive optics

Author: Hugo Nowacki, Jean-Baptiste Le Bouquin, Carole Gouvret, Aurélie Marcotto, Sylvie Robbe Dubois, Karine Perraut, Yves Magnard, Alain Delboulbé, Eric Stadler, Sylvain Guieu, Sylvain Rochat, and Didier Maurel
Subjects: FOS: Physical sciences, Astrophysics - Instrumentation and Methods for Astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM)
Abstract: We present an experiment set to address a standard specification aiming at avoiding local turbulence inside the Coud\'e train of telescopes. Namely, every optical surface should be kept within a 1.5$^\circ$ range around ambient temperature. Such a specification represents an important concern and constraint when developing optical systems for astronomy. Our aim was to test its criticality in the context of the development of the VLTI/NAOMI and VLTI/GRAVITY+ adaptive optics. This experiment has been conducted using the hardware of the future Corrective Optics (CO) of GRAVITY+. Optical measurements were performed in order to observe the evolution of turbulence in front of a flat mirror for which the surface temperature was controlled in a range of $22^\circ$ above ambient temperature. A time-dependent analysis of the turbulence was led along with a spatial analysis. This experiment shows no influence of temperature on local turbulence. It should be noted however that this result is only applicable to the very specific geometry described in this paper, which is representative of an adaptive optics (AO) system located inside the Coud\'e train (facing-down mirror heated on its backface).
Published: 2022
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3. HARMONI at ELT: system analysis and performance estimation of the high-contrast module

Author: Alexis Carlotti, Laurent Jocou, Thibaut Moulin, Patrick Rabou, Alexis Bidot, Adrien Hours, Yves Magnard, Alain Delboulbé, Fabrice Pancher, Élodie Choquet, Arthur Vigan, Mathis Houllé, Kjetil Dohlen, Jean-François Sauvage, Thierry Fusco, Niranjan Thatte, Benoît Neichel, Fraser Clarke, Dave Melotte, Matthias Tecza, Hermine Schnetler, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Laboratoire d'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), Observatoire de la Côte d'Azur (OCA), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), DOTA, ONERA [Salon], ONERA, DOTA, ONERA, Université Paris Saclay [Palaiseau], and ONERA-Université Paris-Saclay
Subjects: ELT, high spectral resolution, [PHYS]Physics [physics], [SPI]Engineering Sciences [physics], exoplanets, [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], direct imaging, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Spectroscopy, high angular resolution, [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM]
Abstract: International audience; HARMONI is the first light visible and near-IR integral field spectrograph for the ELT. It covers a large spectral range from 450nm to 2450nm with resolving powers from 3500 to 18000 and spatial sampling from 60mas to 4mas. It can operate in two Adaptive Optics modes- SCAO (including a High Contrast capability) and LTAOor with NOAO. The project is preparing for Final Design Reviews. The high-contrast module (HCM) has been designed to characterize planets as close as 100mas from their host star (goal: 50mas), and presenting a 1e-6 f lux ratio with it. To do so, it will use (1) a passive atmospheric dispersion corrector, (2) a set of amplitude apodizers and focal plane masks to lower the di↵racted intensity next to the star and attenuate the PSF core, (3) a dedicated Zernike wavefront sensor to track the non-common path aberrations with the SCAO subsystem at a 0.1Hz frequency, and (4) post-processing algorithms that will rely on the temporal and spectral diversity of the IFS data to separate the planetary signals from the noise. This communication details several trade-o↵ analyses involved in the co-design of the hardware of the HCM. It also presents contrast performance estimates that have been derived through an analysis of post-processed, simulated IFS data obtained with an end-to-end numerical model of the HCM and the rest of HARMONI. The respective interests of ADI and molecular mapping are compared in this specific case.
Published: 2022
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4. HARMONI sur l'ELT : un analyseur de front d'onde de Zernike pour le module Haut-Contraste : résultats expérimentaux dans des conditions réalistes d'observation

Author: Adrien Hours, Alexis Carlotti, David Mouillet, Alain Delboulbé, Sylvain Guieu, Laurent Jocou, Thibaut Moulin, Fabrice Pancher, Patrick Rabou, Élodie Choquet, Kjetil Dohlen, Jean François Sauvage, Mamadou N'Diaye, 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), DOTA, ONERA [Salon], ONERA, Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: ELT, [SDU]Sciences of the Universe [physics], FOS: Physical sciences, Astrophysics - Instrumentation and Methods for Astrophysics, OPTIQUE ADAPTATIVE, Instrumentation and Methods for Astrophysics (astro-ph.IM), EXOPLANETE
Abstract: ELT-HARMONI is the first light visible and near-IR integral field spectrograph (IFS) for the ELT. It covers a large spectral range from 450nm to 2450nm with resolving powers from 3500 to 18000 and spatial sampling from 60mas to 4mas. It can operate in two Adaptive Optics modes - SCAO (including a High Contrast capability) and LTAO - or with NOAO. The project is preparing for Final Design Reviews. The High Contrast Module (HCM) will allow HARMONI to perform direct imaging and spectral analysis of exoplanets up to one million times fainter than their host star. Quasi-static aberrations are a limiting factor and must be calibrated as close as possible to the focal plane masks to reach the specified contrast. A Zernike sensor for Extremely Low-level Differential Aberrations (ZELDA) will be used in real-time and closed-loop operation at 0.1Hz frequency for this purpose. Unlike a Shack-Hartmann, the ZELDA wavefront sensor is sensitive to Island and low-wind effects. The ZELDA sensor has already been tested on VLT-SPHERE and will be used in other instruments. Our objective is to adapt this sensor to the specific case of HARMONI. A ZELDA prototype is being both simulated and experimentally tested at IPAG. Its nanometric precision has first been checked in 2020 in the case of slowly evolving, small wavefront errors, and without dispersion nor turbulence residuals. On this experimental basis, we address the performance of the sensor under realistic operational conditions including residuals, mis-centring, dispersion, sensitivity, etc. Atmospheric refraction residuals were introduced by the use of a prism, and turbulence was introduced by a spatial light modulator which is also used to minimise wavefront residuals in a closed loop in the observing conditions expected with HARMONI., 14 pages, 13 figures, SPIE Astronomical Telescopes + Instrumentation (AS22)
Published: 2022
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5. HARMONI at ELT: overview of the capabilities and expected performance of the ELT's first light, adaptive optics assisted integral field spectrograph

Author: Niranjan . Thatte, Dave Melotte, Benoit Neichel, David Le Mignant, Ian Bryson, Fraser Clarke, Vanessa Ferraro-Wood, Thierry Fusco, Oscar Gonzalez, Hermine Schnetler, Matthias Tecza, Sandi Wilson, Alonso Álvarez Urueña, Heribert A. Vilaseca, Santiago Arribas Mocoroa, Gonzalo José Carracedo Carballale, Alejandro Crespo, Alberto Estrada Piqueras, Miriam García García, Cecilia Martínez Martín, Miguel Pereira Santaella, Michele Perna, Javier Piqueras López, Niolas Bouché, Didier Boudon, Eric Daguisé, Karen Disseau, Jérémy J. Fensch, Adrien Girardot, Matthieu Guibert, Aurélien Jarno, Alexandre Jeanneau, Jens-Kristian Krogager, Florence Laurent, Magali Loupias, Jean-Emmanuel Migniau, Laure Piqueras, Alban Remillieux, Johan Richard, Arlette Pecontal, Lisa F. Bardou, David Barr, Sylvain Cetre, Rishi Deshmukh, Sofia Dimoudi, Marc Dubbledam, Andrew Dunn, Dimitra Gadotti, Joss J. Guy, David L. King, David J. Little, Anna McLeod, Simon Morris, Tim Morris, Kieran S. O'Brien, Emily Ronson, Russell Smith, Lazar Staykov, Mark Swinbank, Matthew Townson, Matteo Accardo, Domingo Alvarez Mendez, Elizabeth George, Joshua Hopgood, Derek Ives, Leander Mehrgan, Eric Mueller, Javier Reyes-Moreno, Ralf Conzelmann, Pablo Gutierrez Cheetham, Ángel Alonso-Sánchez, Giuseppina Battaglia, Miguel Angel Cagigas Garcia, Haresh M. Chulani, Graciela C. Delgado García, Patricia Fernández-Izquierdo, Ana Belén Fragoso López, Begoña García-Lorenzo, Alberto Hernández González, Elvio Hernández Suárez, Jose Miguel Herreros Linares, Enrique Joven, Roberto López López, Alejandro Antonio Lujan Gonzalez, Yolanda Martín, Evencio Mediavilla, Saúl Menéndez Mendoza, Luz Maria Montoya Martínez, José Peñate Castro, Álvaro Pérez, José Luis Rasilla, Rafael Rebolo-López, Luis Fernando Rodríguez-Ramos, Afrodisio Vega Moreno, Teodora Viera-Curbelo, Natacha Zanon Dametto, Alexis Carlotti, Jean-Jacques Correia, Stéphane Curaba, Alain Delboulbé, Sylvain Guieu, Adrien Hours, Zoltan Hubert, Laurent Jocou, Yves Magnard, Thibaut Moulin, Fabrice Pancher, Patrick Rabou, Eric Stadler, Maxime Vérove, Thierry Contini, Marie Larrieu, Olivier Boebion, Yan Fantéï-Caujolle, Daniel Lecron, Sylvain Rousseau, Philippe Amram, Olivier Beltramo-Martin, William Bon, Anne Bonnefoi, William Ceria, Zalpha Challita, Yannick Charles, Elodie Choquet, Carlos Correia, Anne Costille, Kjetil Dohlen, Franck Ducret, Kacem El Hadi, Jean-Luc Gach, Jean-Luc Gimenez, Olivier Groussin, Marc Jaquet, Pierre Jouve, Fabrice Madec, Felipe Pedreros Bustos, Edgard Renault, Patrice Sanchez, Arthur Vigan, Pascal Vola, Annie Zavago, Romain Fétick, Caroline Lim, Cyril Petit, Jean-Francois Sauvage, Nicolas Védrenne, Fehim Taha Bagci, Martin E. Caldwell, Ellis Elliott, Peter Hiscock, Emma Johnson, Murali Nalagatla, Aristea Seitis, Mark Wells, Martin Black, Charlotte Z. Bond, Saskia Brierley, Kenneth Campbell, Neil Campbell, James Carruthers, William Cochrane, Chris Evans, Joel Harman, William Humphreys, Thomas Louth, Chris Miller, David Montgomery, Meenu Murali, John Murray, Norman O'Malley, Ruben Sanchez-Janssen, Noah Schwartz, Patrick Smith, Jonathan Strachan, Stephen Todd, Stuart Watt, Martyn Wells, Asim Yaqoob, Eric Bell, Oleg O. Gnedin, Kayhan Gultekin, Mario Mateo, Michael Meyer, Munadi Ahmad, Jayne Birkby, Michael Booth, Michele Cappellari, Edgar Castillo Dominguez, Jorge Chao Ortiz, David Gooding, Kearn Grisdale, Andrea Hidalgo Valadez, Laurence Hogan, James Kariuki, Ian Lewis, Adam Lowe, Zeynep Ozer, Laurence Routledge, Dimitra Rigopoulou, Alec York, 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), DOTA, ONERA, Université Paris Saclay [Palaiseau], ONERA-Université Paris-Saclay, DOTA, ONERA, Université Paris Saclay [Châtillon], DOTA, ONERA [Salon], and ONERA
Subjects: ELT, [PHYS]Physics [physics], [SPI]Engineering Sciences [physics], [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], OPTIQUE ADAPTATIVE, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM]
Abstract: International audience; HARMONI is the first light, adaptive optics assisted, integral field spectrograph for the European Southern Observatory’s Extremely Large Telescope (ELT). A work-horse instrument, it provides the ELT’s diffraction limited spectroscopic capability across the near-infrared wavelength range. HARMONI will exploit the ELT’s unique combination of exquisite spatial resolution and enormous collecting area, enabling transformational science. The design of the instrument is being finalized, and the plans for assembly, integration and testing are being detailed. We present an overview of the instrument’s capabilities from a user perspective, and provide a summary of the instrument’s design. We also include recent changes to the project, both technical and programmatic, that have resulted from red-flag actions. Finally, we outline some of the simulated HARMONI observations currently being analyzed.
Published: 2022
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6. HARMONI at ELT: development of the high-contrast module

Author: Laurent Jocou, Patrick Rabou, Thibaut Moulin, Yves Magnard, Adrien Hours, Fabrice Pancher, Sylvain Guieu, Alexis Carlotti, Alain Delboulbé, Maxime Vérove, Eric Stadler, Didier Maurel, Sylvain Rochat, François Hénault, Kjetil Dohlen, Niranjan Thatte, Benoit Neichel, Pascal Vola, Fraser Clarke, Dave Melotte, Matthias Tecza, Hermine Schnetler, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Laboratoire d'Astrophysique de Marseille (LAM), and 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)
Subjects: [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM]
Abstract: International audience
Published: 2022
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7. Laboratory Experiments Confirm the Polarization of Auroral Emissions

Author: Slava Bourgeois, Léo Bosse, Jean Lilensten, Nicolas Gillet, Stéphane Curaba, Alain Delboulbé, Sylvain Rochat, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), Université Grenoble Alpes (UGA), and Centre National de la Recherche Scientifique (CNRS)
Subjects: [PHYS.ASTR.IM]Physics [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], Geophysics, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], General Earth and Planetary Sciences, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2022
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8. The polarisation of auroral emissions: A tracer of the E region ionospheric currents

Author: Léo Bosse, Jean Lilensten, Magnar G. Johnsen, Nicolas Gillet, Sylvain Rochat, Alain Delboulbé, Stephane Curaba, Yasunobu Ogawa, Philippe Derverchère, Sébastien Vauclair, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Institut des Sciences de la Terre (ISTerre), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel-Université Grenoble Alpes (UGA), Université Grenoble Alpes (UGA), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)
Subjects: Atmospheric Science, Aurora, EISCAT, Space and Planetary Science, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Polarisation
Abstract: International audience; It is now established that auroral emissions as measured from the ground are polarised. The question of the information given by this polarisation is still to be explored. This article shows the results of a coordinated campaign between an optical polarimeter and several ground-based instruments, including magnetometers, the EISCAT VHF radar, and complementary luminance meters in the visible domain (Ninox). We show that in the E region, the polarisation is a potential indicator of the ionospheric currents, velocity, and dynamics.
Published: 2022
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9. At the source of the polarisation of auroral emissions: experiments and modeling

Author: Léo Bosse, Jean Lilensten, Nicolas Gillet, Colette Brogniez, Olivier Pujol, Sylvain Rochat, Alain Delboulbé, Stéphane Curaba, Magnar Gullikstad Johnsen, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Université Grenoble Alpes (UGA), Qualité de vie et Santé psychologique [Tours] (QualiPsy - E.E. 1901), Université de Tours (UT), Laboratoire d’Optique Atmosphérique - UMR 8518 (LOA), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Tromsø Geophysical Observatory (TGO), and The Arctic University of Norway [Tromsø, Norway] (UiT)
Subjects: Ionospheric environment, Atmospheric Science, Space and Planetary Science, Radiative transfer, Linear polarisation, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Auroral lights
Abstract: A polarised radiative transfer model (POMEROL) has been developed to compute the polarisation measured by a virtual instrument in a given nocturnal environment. This single-scattering model recreates real-world conditions (among them atmospheric and aerosol profiles, light sources with complex geometries at the ground and in the sky, terrain obstructions). It has been successfully tested at mid-latitudes where sky emissions are of weak intensity. We show a series of comparisons between POMEROL predictions and polarisation measurements during two field campaigns in the auroral zone, in both quiet and active conditions. These comparisons show the strength of the model to assess the aerosol characteristics in the lower atmosphere by using a mesospheric line. They also show that three main upper atmosphere emissions must be polarised: the green atomic oxygen line at 557.7 nm and the 1stN2+negative band at 391.4 nm (purple) and 427.8 nm (blue). This polarisation can be either created directly at the radiative de-excitation or may occur when the non-polarised emission crosses the ionospheric currents. We provide some of the potentialities it offers in the frame of space weather. These require refinements of the preliminary modeling approach considered in the present study.
Published: 2022
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10. TOI-269 b: an eccentric sub-Neptune transiting a M2 dwarf revisited with ExTrA

Author: Sara Seager, Eric B. Ting, Felipe Murgas, Nicholas M. Law, D. Maurel, S. Curaba, Tianjun Gan, S. Rochat, Richard G. West, George R. Ricker, Francesco Pepe, René Doyon, P. Kern, Coel Hellier, Jon M. Jenkins, Thibaut Moulin, I. C. Leão, G. Gaisne, Caroline Dorn, Xavier Bonfils, Laurent Jocou, Yves Magnard, J.-J. Correia, Eric Stadler, P. Rabou, C. Melo, Joshua N. Winn, C. Ziegler, J. D. Twicken, C. Lovis, Karen A. Collins, Nicola Astudillo-Defru, B. L. Canto Martins, Aurélien Wyttenbach, X. Delfosse, Alain Roux, Kevin I. Collins, Alain Delboulbé, J. F. Otegi, David R. Anderson, Jose-Manuel Almenara, William Waalkes, Ravit Helled, Marion Cointepas, François Bouchy, J. R. De Medeiros, Roland Vanderspek, Étienne Artigau, David Charbonneau, Pedro Figueira, T. Forveille, David W. Latham, L. Gluck, David R. Rodriguez, Andrew W. Mann, A. Wunsche, S. Lafrasse, Nuno C. Santos, Damien Ségransan, Rodrigo F. Díaz, Stéphane Udry, Philippe Feautrier, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), Departamento de Matemática y Fı́sica Aplicadas [Concepcion] (DMFA), Universidad Católica de la Santísima Concepción (UCSC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), and Université de Montréal (UdeM)
Subjects: 010504 meteorology & atmospheric sciences, media_common.quotation_subject, FOS: Physical sciences, Astrophysics, 01 natural sciences, Transmission spectroscopy, Photometry (optics), Neptune, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Eccentricity (behavior), Spectroscopy, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, media_common, Physics, Earth and Planetary Astrophysics (astro-ph.EP), [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astronomy and Astrophysics, Radius, Orbital period, Exoplanet, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Earth and Planetary Astrophysics
Abstract: We present the confirmation of a new sub-Neptune close to the transition between super-Earths and sub-Neptunes transiting the M2 dwarf TOI- 269 (TIC 220479565, V = 14.4 mag, J = 10.9 mag, Rstar = 0.40 Rsun, Mstar = 0.39 Msun, d = 57 pc). The exoplanet candidate has been identified in multiple TESS sectors, and validated with high-precision spectroscopy from HARPS and ground-based photometric follow-up from ExTrA and LCO-CTIO. We determined mass, radius, and bulk density of the exoplanet by jointly modeling both photometry and radial velocities with juliet. The transiting exoplanet has an orbital period of P = 3.6977104 +- 0.0000037 days, a radius of 2.77 +- 0.12 Rearth, and a mass of 8.8 +- 1.4 Mearth. Since TOI-269 b lies among the best targets of its category for atmospheric characterization, it would be interesting to probe the atmosphere of this exoplanet with transmission spectroscopy in order to compare it to other sub-Neptunes. With an eccentricity e = 0.425+0.082-0.086, TOI-269 b has one of the highest eccentricities of the exoplanets with periods less than 10 days. The star being likely a few Gyr old, this system does not appear to be dynamically young. We surmise TOI-269 b may have acquired its high eccentricity as it migrated inward through planet-planet interactions., Comment: 23 pages, 16 figures, Accepted for publication in A&A
Published: 2021
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11. The SPHERE infrared survey for exoplanets (SHINE)

Author: Kjetil Dohlen, André Müller, C. Petit, A. Pavlov, Valentina D'Orazi, Alexandre Emsenhuber, Alice Zurlo, E. Sissa, Ronald Roelfsema, Norbert Hubin, Marc Jaquet, Gabriel-Dominique Marleau, Gérard Rousset, Anthony Cheetham, H. Le Coroller, Alain Roux, S. Brown Sevilla, Enrico Giro, Faustine Cantalloube, Anne Costille, Janis Hagelberg, Jean-Luc Beuzit, Thierry Fusco, P. Gigan, Julien Charton, Markus Feldt, A. Bazzon, Ruben Asensio-Torres, C. Fontanive, Zahed Wahhaj, Anne-Lise Maire, Th. Henning, M. Carle, Marcel Carbillet, J. Ramos, Matthias Samland, Alain Origne, Raffaele Gratton, Arthur Vigan, Stéphane Udry, H. M. Schmid, Pierre Baudoz, Patrice Martinez, Markus Janson, O. Möller-Nilsson, L. Weber, Marcos Suarez, Cecile Gry, Michael Meyer, Sergio Messina, N. Engler, Emmanuel Hugot, Arnaud Sevin, A. Boccaletti, Alexander J. Bohn, P. Rabou, Julien Girard, T. Moulin, Jacopo Antichi, Beth Biller, F. Rigal, David Mouillet, C. Soenke, F. Madec, Riccardo Claudi, Silvano Desidera, M. Llored, E. Cascone, Daniela Fantinel, D. Gisler, R. Galicher, J. Baudrand, T. O. B. Schmidt, J. Pragt, Mickael Bonnefoy, D. Le Mignant, Mariangela Bonavita, Philippe Delorme, Jean-François Sauvage, Francois Wildi, Duncan Forgan, C. Mordasini, L. Gluck, Denis Perret, E. L. Rickman, Carsten Dominik, C. Lazzoni, E. Lagadec, Roxanne Ligi, Andrea Baruffolo, Lyu Abe, Gael Chauvin, A-M. Lagrange, Massimo Turatto, Pascal Puget, Philippe Feautrier, Yves Magnard, Bernardo Salasnich, Maud Langlois, V. De Caprio, D. Maurel, M. Kasper, Ken Rice, Dino Mesa, S. Rochat, C. Moutou, C. Perrot, Alain Delboulbé, P. Blanchard, François Ménard, Eric Stadler, Low Energy Astrophysics (API, FNWI), INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Center for Space and Habitability (CSH), University of Bern, University of Edinburgh, Max Planck Institute for Radio Astronomy, Eberhard Karls Universität Tübingen = Eberhard Karls University of Tuebingen, Lunar and Planetary Laboratory [Tucson] (LPL), University of Arizona, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Scottish Universities Physics Alliance (SUPA), Max Planck Institute for Astronomy (MPIA), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Geneva Observatory, Université de Genève = University of Geneva (UNIGE), Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astronomico di Brera (OAB), Department of Biochemistry and Molecular Biology, Mayo Clinic, INAF - Osservatorio Astrofisico di Catania (OACT), Canada-France-Hawaii Telescope Corporation (CFHT), National Research Council of Canada (NRC)-Centre National de la Recherche Scientifique (CNRS)-University of Hawai'i [Honolulu] (UH), 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), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institute for Particle Physics and Astrophysics [ETH Zürich] (IPA), Department of Physics [ETH Zürich] (D-PHYS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), CHU Tenon [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), CHU Pitié-Salpêtrière [AP-HP], Laboratoire des biomolécules (LBM UMR 7203), Chimie Moléculaire de Paris Centre (FR 2769), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Département de Chimie - ENS Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Hippolyte Fizeau (FIZEAU), INAF - Osservatorio Astronomico di Capodimonte (OAC), DOTA, ONERA, Université Paris Saclay [Châtillon], ONERA-Université Paris-Saclay, Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Radboud University [Nijmegen], European Southern Observatory (ESO), Environnements et Paléoenvironnements OCéaniques (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), NASA Goddard Space Flight Center (GSFC), Institut de Recherche pour le Développement (IRD), Centre Hospitalier Henri Duffaut (Avignon), ANR-16-CE31-0013,PLANET-FORMING-DISKS,De meilleurs modèles pour de meilleures données(2016), University of Michigan [Ann Arbor], University of Michigan System, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Centre for Exoplanet Science, Space Sciences, Technologies and Astrophysics Research Institute (STAR), Université de Liège, Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), Laboratoire Franco-Chilien d'Astronomie (LFCA), Universidad de Concepción [Chile]-Pontificia Universidad Católica de Chile (UC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Universidad de Chile, University of Geneva [Switzerland], 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-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Anton Pannekoek Institute for Astronomy, University of Amsterdam [Amsterdam] (UvA), Observatoire de la Côte d'Azur (OCA), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Universidad Diego Portales [Santiago] (UDP), Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Radboud university [Nijmegen], DAAA, ONERA, Université Paris Saclay [Meudon], Eberhard Karls Universität Tübingen, Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Lagrange, Université Côte d'Azur, Observatoire de la Côte d'Azur, CNRS., Laboratoire de Biomécanique et Mécanique des Chocs (LBMC UMR T9406 ), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Université Gustave Eiffel, 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 Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), CHU Tenon [APHP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université, Département Médico-Universitaire APPROCHES, Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université-Sorbonne Université (SU), Sorbonne Université-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Institut National de la Santé et de la Recherche Médicale (INSERM)-Chimie Moléculaire de Paris Centre (FR 2769), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), 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)-Centre National de la Recherche Scientifique (CNRS)-Département de Chimie - ENS Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, ARCHEORIENT - Environnements et sociétés de l'Orient ancien (Archéorient), Université Lumière - Lyon 2 (UL2)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE), Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux (IPREM), Université de Pau et des Pays de l'Adour (UPPA)-Centre National de la Recherche Scientifique (CNRS), Centre d'étude des environnements terrestre et planétaires (CETP), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Universidad de Chile = University of Chile [Santiago] (UCHILE)-Pontificia Universidad Católica de Chile (UC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Universidad de Concepción - University of Concepcion [Chile], Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Département de Chimie - ENS Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Chimie Moléculaire de Paris Centre (FR 2769), Institut de Chimie du CNRS (INC)-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)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM), and Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: astro-ph.SR, astro-ph.GA, Brown dwarf, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Stellar classification, 01 natural sciences, Planet, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, planets and satellites: formation, 10. No inequality, infrared: planetary systems, 010303 astronomy & astrophysics, planetary systems, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, Earth and Planetary Astrophysics (astro-ph.EP), Physics, Very Large Telescope, methods: statistical, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, techniques: high angular resolution, Astronomy and Astrophysics, Planetary system, Astrophysics - Astrophysics of Galaxies, Exoplanet, Accretion (astrophysics), Stars, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), astro-ph.EP, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Earth and Planetary Astrophysics
Abstract: The SHINE project is a 500-star survey performed with SPHERE on the VLT for the purpose of directly detecting new substellar companions and understanding their formation and early evolution. Here we present an initial statistical analysis for a subsample of 150 stars that are representative of the full SHINE sample. Our goal is to constrain the frequency of substellar companions with masses between 1 and 75 MJup and semimajor axes between 5 and 300 au. We adopt detection limits as a function of angular separation from the survey data for all stars converted into mass and projected orbital separation using the BEX-COND-hot evolutionary tracks and known distance to each system. Based on the results obtained for each star and on the 13 detections in the sample, we use a MCMC tool to compare our observations to two different types of models. The first is a parametric model based on observational constraints, and the second type are numerical models that combine advanced core accretion and gravitational instability planet population synthesis. Using the parametric model, we show that the frequencies of systems with at least one substellar companion are $23.0_{-9.7}^{+13.5}\%$, $5.8_{-2.8}^{+4.7}\%$, and $12.6_{-7.1}^{+12.9}\%$ for BA, FGK, and M stars, respectively. We also demonstrate that a planet-like formation pathway probably dominates the mass range from 1-75 MJup for companions around BA stars, while for M dwarfs, brown dwarf binaries dominate detections. In contrast, a combination of binary star-like and planet-like formation is required to best fit the observations for FGK stars. Using our population model and restricting our sample to FGK stars, we derive a frequency of $5.7_{-2.8}^{+3.8}\%$, consistent with predictions from the parametric model. More generally, the frequency values that we derive are in excellent agreement with values obtained in previous studies., Comment: 24 pages, 14 figures, 3 tables. Accepted for publication in A&A
Published: 2020
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12. On the nightglow polarisation for space weather exploration

Author: Alain Roux, Nicolas Gillet, Stephane Curaba, Nicolas Le Bihan, Camille Noûs, Léo Bosse, Magnar Gullikstad Johnsen, Yves Magnard, Jean Lilensten, Sylvain Rochat, Pierre-Olivier Amblard, Maxime Nabon, Alain Delboulbé, U. P. Løvhaug, Hanane Marif, Frédérique Auriol, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Institut des Sciences de la Terre (ISTerre), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel-Université Grenoble Alpes (UGA), Tromsø Geophysical Observatory (TGO), The Arctic University of Norway [Tromsø, Norway] (UiT), GIPSA Pôle Géométrie, Apprentissage, Information et Algorithmes (GIPSA-GAIA), Grenoble Images Parole Signal Automatique (GIPSA-lab), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Université des Sciences et de la Technologie Houari Boumediene = University of Sciences and Technology Houari Boumediene [Alger] (USTHB), Laboratoire d’Optique Atmosphérique - UMR 8518 (LOA), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire Cogitamus, Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), The Arctic University of Norway (UiT), and Université des Sciences et de la Technologie Houari Boumediene [Alger] (USTHB)
Subjects: Atmospheric Science, Electron density, 010504 meteorology & atmospheric sciences, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], Astrophysics, polarisation, lcsh:QC851-999, Space weather, 01 natural sciences, VDP::Mathematics and natural science: 400::Physics: 430, Troposphere, Atmosphere, 0103 physical sciences, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Line (formation), Physics, VDP::Matematikk og Naturvitenskap: 400::Fysikk: 430, Airglow, aurora, [PHYS.PHYS.PHYS-SPACE-PH]Physics [physics]/Physics [physics]/Space Physics [physics.space-ph], 13. Climate action, Space and Planetary Science, Polar, lcsh:Meteorology. Climatology, Ionosphere
Abstract: We present here observations of the polarisation of four auroral lines in the auroral oval and in the polar cusp using a new ground polarimeter called Petit Cru. Our results confirm the already known polarisation of the red line, and show for the first time that the three other lines observed here (namely 557.7 nm, 391.4 nm and 427.8 nm) are polarised as well up to a few percent. We show that in several circumstances, this polarisation is linked to the local magnetic activity and to the state of the ionosphere through the electron density measured with EISCAT. However, we also show that the contribution of light pollution from nearby cities via scattering can not be ignored and can play an important role in polarisation measurements. This series of observations questions the geophysical origin of the polarisation. It also leaves open its relation to the magnetic field orientation and to the state of both the upper atmosphere and the troposphere.
Published: 2020
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13. The MAORY laser guide star wavefront sensor: design status

Author: Christophe Verinaud, Roberto Ragazzoni, Sylvain Oberti, Sylvain Rochat, Fausto Cortecchia, L. Gluck, Jean-Jacques Correia, Michele Bellazzini, Carmelo Arcidiacono, Sylvain Douté, Eric Stadler, Simone Esposito, Estelle Moraux, Lorenzo Busoni, T. Moulin, Paolo Ciliegi, Emiliano Diolaiti, Alain Delboulbé, Philippe Feautrier, Laurent Jocou, Yves Magnard, Laura Schreiber, Gael Chauvin, Patrick Rabou, ITA, and FRA
Subjects: Wavefront, business.industry, Computer science, Field of view, Wavefront sensor, First light, Laser, law.invention, Optics, Laser guide star, law, Extremely Large Telescope, business, Spectrograph
Abstract: MAORY will be the multi-adaptive optics module feeding the high resolution camera and spectrograph MICADO at the Extremely Large Telescope (ELT) first light. In order to ensure high and homogeneous image quality over the MICADO field of view and high sky coverage, the baseline is to operate wavefront sensing using six Sodium Laser Guide Stars. The Laser Guide Star Wavefront Sensor (LGS WFS) is the MAORY sub-system devoted to real-time measurement of the high order wavefront distortions. In this paper we describe the MAORY LGS WFS current design, including opto-mechanics, trade-offs and possible future improvements.
Published: 2018
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14. NAOMI: the adaptive optics for the auxiliary telescopes of VLTI

Author: Johan Kosmalski, Jean-Baptiste Le Bouquin, Javier Reyes, J. P. Kirchbauer, Alain Delboulbé, Sebastien Egner, Luigi Andolfato, Yves Magnard, Alexander Meister, Christophe Dupuy, Pascaline Darré, Jean-Philippe Berger, Luca Pasquini, Norbert Hubin, Johann Kolb, Roderick Dembet, Frédéric Gonté, Eric Stadler, T. Moulin, Nicolas Schuhler, Julien Woillez, Pierre Bourget, S. Guieu, Guillermo Valdes, Christian Stephan, S. Rochat, Jaime Alonso, Stefan Huber, Peter Krempl, Laurent Jocou, Pavel Shchekaturov, Pablo Gutierrez, Pierre Haguenauer, Christophe Verinaud, and Emmanuel Aller-Carpentier
Subjects: Interferometry, Optics, Computer science, business.industry, Strehl ratio, System testing, Adaptive optics, business, Deformable mirror
Abstract: The New Adaptive Optics Module for Interferometry (NAOMI) is ready to be installed at the 1.8-metre Auxiliary Telescopes (ATs) at ESO Paranal. NAOMI will make the existing interferometer performance less dependent on the seeing conditions. Fed with higher and more stable Strehl, the fringe tracker will achieve the fringe stability necessary to reach the full performance of the second-generation instruments GRAVITY and MATISSE. All four ATs will be equipped between September and November 2018 with a Deformable mirror (ALPAO DM-241), a 4*4 Shack– Hartmann adaptive optics system operating in the visible and an RTC based on SPARTA Light. During the last 6 months thorough system test has been made in laboratory to demonstrate the Adaptive Optics and chopping capability of NAOMI.
Published: 2018
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15. Discovery of a brown dwarf companion to the star HIP 64892

Author: Jacopo Antichi, L. Weber, E. Sissa, Johan Olofsson, H. Le Coroller, Markus Kasper, Damien Ségransan, Alain Roux, T. Buey, Alice Zurlo, Cyril Petit, Alain Delboulbé, Andrea Baruffolo, Thomas Henning, Arnaud Sevin, P. Blanchard, Ronald Roelfsema, Daniela Fantinel, Alain Origne, R. Ligi, Anne Costille, M. Carle, Kjetil Dohlen, François Ménard, Bernardo Salasnich, Maud Langlois, Pierre Baudoz, V. De Caprio, Enrico Giro, D. Maurel, Lyu Abe, Markus Janson, O. Möller-Nilsson, Raffaele Gratton, Jean-Luc Beuzit, Riccardo Claudi, Beth Biller, Eric Stadler, Valentina D'Orazi, Massimo Turatto, Marc Jaquet, Joshua E. Schlieder, Pascal Puget, Taisiya Kopytova, Yves Magnard, Arthur Vigan, C. Soenke, Anthony Cheetham, Anne-Lise Maire, Patrice Martinez, D. Le Mignant, Gérard Rousset, A. Pavlov, Norbert Hubin, M. Keppler, Anne-Marie Lagrange, Emmanuel Hugot, Eric Lagadec, Hubert Klahr, Daniel Rouan, Dino Mesa, Michael Meyer, Thierry Fusco, Janis Hagelberg, Markus Feldt, Philippe Feautrier, Joany Andreina Manjarres Ramos, Quentin Kral, M. Llored, E. Cascone, Marcel Carbillet, S. Rochat, T. O. B. Schmidt, Mickael Bonnefoy, T. Moulin, S. Peretti, P. Rabou, David Mouillet, L. Gluck, J. Pragt, Gael Chauvin, F. Madec, Jean-François Sauvage, Francois Wildi, C. Mordasini, Denis Perret, Carsten Dominik, Anthony Boccaletti, F. Rigal, Marcos Suarez, Stéphane Udry, Silvano Desidera, Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), 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-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - 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), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Universidad de Chile, Universidad de Valparaiso [Chile], Stockholm University, University of Edinburgh, Instituto de Astronomia y ciencias Planetarias de Atacama (INCT), Universidad de Atacama, University of Cambridge [UK] (CAM), NASA Goddard Space Flight Center (GSFC), University of Bern, Universidad Diego Portales [Santiago] (UDP), Institute for Particle Physics and Astrophysics [ETH Zürich] (IPA), Department of Physics [ETH Zürich] (D-PHYS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Department of Mathematics - University of Michigan, University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Arizona State University [Tempe] (ASU), Ural Federal University [Ekaterinburg] (UrFU), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astrofisico di Arcetri (OAA), INAF - Osservatorio Astronomico di Capodimonte (OAC), DOTA, ONERA, Université Paris Saclay (COmUE) [Châtillon], ONERA-Université Paris Saclay (COmUE), European Southern Observatory (ESO), NOVA Optical Infrared Instrumentation Group, European Southern Observatory [Santiago] (ESO), Université de Genève = University of Geneva (UNIGE), École normale supérieure de Lyon (ENS de 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), Universidad de Chile = University of Chile [Santiago] (UCHILE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich)-Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), DOTA, ONERA, Université Paris Saclay [Châtillon], ONERA-Université Paris-Saclay, 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), Low Energy Astrophysics (API, FNWI), Department of Physical Geography and Ecosystem Science [Lund], Lund University [Lund], Institute for Astronomy [Edinburgh] (IfA), Geneva Observatory, Department of Biochemistry and Molecular Biology, Mayo Clinic, Observatoire de Paris, Université Paris sciences et lettres (PSL), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
Subjects: [PHYS.ASTR.IM]Physics [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], INDIVIDUAL: HIP 64892 [STARS], HIGH ANGULAR RESOLUTIONS [TECHNIQUES], 530 Physics, Astrophysics::High Energy Astrophysical Phenomena, BROWN DWARFS, FOS: Physical sciences, Library science, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, DETECTIONS [PLANETS AND SATELLITES], OPTIQUE ADAPTATIVE, 01 natural sciences, Techniques: high angular resolution, VLT, 0103 physical sciences, DETECTION [PLANETS AND SATELLITES], Astrophysics::Solar and Stellar Astrophysics, European commission, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, Stars: brown dwarfs individual: HIP 64892, HIGH ANGULAR RESOLUTION [TECHNIQUES], Earth and Planetary Astrophysics (astro-ph.EP), Physics, ASTRONOMIE, INDIVIDUAL [STARS], 010308 nuclear & particles physics, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], 520 Astronomy, EFFECTIVE TEMPERATURE, Astronomy and Astrophysics, Planets and satellites: detection, 500 Science, 620 Engineering, EVOLUTIONARY MODELS, Astrophysics - Solar and Stellar Astrophysics, FORMATION AND EVOLUTIONS, Space and Planetary Science, ATMOSPHERES [SATELLITES], SPECTRAL ENERGY DISTRIBUTION, Christian ministry, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], SATELLITES, STARS, Astrophysics - Earth and Planetary Astrophysics, PLANETS
Abstract: We report the discovery of a bright, brown dwarf companion to the star HIP 64892, imaged with VLT/SPHERE during the SHINE exoplanet survey. The host is a B9.5V member of the Lower-Centaurus-Crux subgroup of the Scorpius Centaurus OB association. The measured angular separation of the companion ($1.2705\pm0.0023$") corresponds to a projected distance of $159\pm12$ AU. We observed the target with the dual-band imaging and long-slit spectroscopy modes of the IRDIS imager to obtain its SED and astrometry. In addition, we reprocessed archival NACO L-band data, from which we also recover the companion. Its SED is consistent with a young (, Comment: 12 pages, 11 figures, accepted for publication in A&A
Published: 2018
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16. Imaging radial velocity planets with SPHERE

Author: Anne-Marie Lagrange, Clément Perrot, Claire Moutou, Arthur Vigan, P. J. Potiron, Dino Mesa, Jose Ramos, C. Petit, Esther Buenzli, Mickael Bonnefoy, Matthias Meyer, Tanmay Bhowmik, Markus Feldt, Silvano Desidera, Maud Langlois, Anne-Lise Maire, Markus Janson, Graeme Salter, C. Lazzoni, T. Schmidt, Jean-Luc Beuzit, Alain Delboulbé, M. Cudel, Beth Biller, Mariangela Bonavita, Wolfgang Brandner, S. Peretti, Sylvain Rochat, Janis Hagelberg, Valentina D'Orazi, Anthony Boccaletti, Alice Zurlo, Baptiste Lavie, Sergio Messina, Raffaele Gratton, F. Rigal, Gael Chauvin, David Mouillet, J. Lannier, E. Sissa, Universidad Diego Portales [Santiago] (UDP), 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), Instituto de Astronomia y ciencias Planetarias de Atacama (INCT), Universidad de Atacama, INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), INAF - Osservatorio Astrofisico di Catania (OACT), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), University of Edinburgh, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Institute for Particle Physics and Astrophysics [ETH Zürich] (IPA), Department of Physics [ETH Zürich] (D-PHYS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich)-Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), Stockholm University, Centre de Recherche Astrophysique de Lyon (CRAL), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), University of Michigan [Ann Arbor], University of Michigan System, Observatoire de la Côte d'Azur (OCA), Centre National de la Recherche Scientifique (CNRS), DOTA, ONERA, Université Paris Saclay [Palaiseau], ONERA-Université Paris-Saclay, Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), DOTA, ONERA, Université Paris Saclay (COmUE) [Palaiseau], ONERA-Université Paris Saclay (COmUE), 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 de Genève = University of Geneva (UNIGE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: FOS: Physical sciences, spectrographs -methods: data analysis [Instrumentation], Astrophysics, 01 natural sciences, GJ 676A, 010309 optics, ETOILE, [SPI]Engineering Sciences [physics], RADIAL VELOCITY, individual: HD142 [Stars], Planet, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, ANALYSE DONNEES, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Earth and Planetary Astrophysics (astro-ph.EP), Physics, [PHYS]Physics [physics], SPECTROGRAPHE, radial velocities [Techniques], imaging spectroscopy [Techniques], IMAGING SPECTROSCOPY, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, Planetary system, Exoplanet, Starlight, Radial velocity, Stars, Orbit, Planetary systems, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, [SDU]Sciences of the Universe [physics], HD39091, HIP 70849, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, SYSTEME PLANETAIRE, Astrophysics - Earth and Planetary Astrophysics, Data reduction
Abstract: We present observations with the planet finder SPHERE of a selected sample of the most promising radial velocity (RV) companions for high-contrast imaging. Using a Monte Carlo simulation to explore all the possible inclinations of the orbit of wide RV companions, we identified the systems with companions that could potentially be detected with SPHERE. We found the most favorable RV systems to observe are : HD\,142, GJ\,676, HD\,39091, HIP\,70849, and HD\,30177 and carried out observations of these systems during SPHERE Guaranteed Time Observing (GTO). To reduce the intensity of the starlight and reveal faint companions, we used Principle Component Analysis (PCA) algorithms alongside angular and spectral differential imaging. We injected synthetic planets with known flux to evaluate the self-subtraction caused by our data reduction and to determine the 5$\sigma$ contrast in the J band $vs$ separation for our reduced images. We estimated the upper limit on detectable companion mass around the selected stars from the contrast plot obtained from our data reduction. Although our observations enabled contrasts larger than 15 mag at a few tenths of arcsec from the host stars, we detected no planets. However, we were able to set upper mass limits around the stars using AMES-COND evolutionary models. We can exclude the presence of companions more massive than 25-28 \MJup around these stars, confirming the substellar nature of these RV companions., Comment: 14 pages, 11 figures, accepted by MNRAS
Published: 2018
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17. Structure of Herbig AeBe disks at the milliarcsecond scale: A statistical survey in the H band using PIONIER-VLTI

Author: Olivier Absil, Michel Tallon, Laurent Jocou, Attila Juhasz, Bernard Lazareff, Alain Delboulbé, Karine Perraut, J.-B. Le Bouquin, Wesley A. Traub, John D. Monnier, Andrea Isella, François Ménard, Jacques Kluska, Myriam Benisty, T. Moulin, Stefan Kraus, Rafael Millan-Gabet, R. Lachaume, Gilles Duvert, Fabien Baron, S. Rochat, G. Zins, C. Pinte, Fabien Malbet, Chris Koen, W. F. Thi, Éric Thiébaut, Ferréol Soulez, Jean-Phillipe Berger, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), University of the Western Cape, Max-Planck-Institut für Extraterrestrische Physik (MPE), Université de Liège, Georgia State University, University System of Georgia (USG), INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), Institute of Astronomy [Cambridge], University of Cambridge [UK] (CAM), University of Exeter, California Institute of Technology (CALTECH), University of Michigan [Ann Arbor], University of Michigan System, 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), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), California Institute of Technology (CALTECH)-NASA, University of the Western Cape (UWC), and École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL)
Subjects: FOS: Physical sciences, Scale (descriptive set theory), Context (language use), Astrophysics, stars: pre-main sequence, Ring (chemistry), 01 natural sciences, circumstellar matter, techniques: photometric, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, Physics, stars: variables: T Tauri, 010308 nuclear & particles physics, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Herbig Ae/Be, Astronomy and Astrophysics, Radius, [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], Interferometry, Stars, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, techniques: interferometric, Sublimation (phase transition), Halo, Astrophysics::Earth and Planetary Astrophysics
Abstract: Context. It is now generally accepted that the near-infrared excess of Herbig AeBe stars originates in the dust of a circumstellar disk. Aims. The aims of this article are to infer the radial and vertical structure of these disks at scales of order one au, and the properties of the dust grains. Methods. The program objects (51 in total) were observed with the H-band (1.6micron) PIONIER/VLTI interferometer. The largest baselines allowed us to resolve (at least partially) structures of a few tenths of an au at typical distances of a few hundred parsecs. Dedicated UBVRIJHK photometric measurements were also obtained. Spectral and 2D geometrical parameters are extracted via fits of a few simple models: ellipsoids and broadened rings with azimuthal modulation. Model bias is mitigated by parallel fits of physical disk models. Sample statistics were evaluated against similar statistics for the physical disk models to infer properties of the sample objects as a group. Results. We find that dust at the inner rim of the disk has a sublimation temperature Tsub~1800K. A ring morphology is confirmed for approximately half the resolved objects; these rings are wide delta_r>=0.5. A wide ring favors a rim that, on the star-facing side, looks more like a knife edge than a doughnut. The data are also compatible with a the combination of a narrow ring and an inner disk of unspecified nature inside the dust sublimation radius. The disk inner part has a thickness z/r~0.2, flaring to z/r~0.5 in the outer part. We confirm the known luminosity-radius relation; a simple physical model is consistent with both the mean luminosity-radius relation and the ring relative width; however, a significant spread around the mean relation is present. In some of the objects we find a halo component, fully resolved at the shortest interferometer spacing, that is related to the HAeBe class., 41 pages. 23 figures. Four appendices
Published: 2017
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18. A detector interferometric calibration experiment for high precision astrometry

Author: Mike Shao, François Hénault, M. Donati, A. Léger, Eric Stadler, C. Ketchazo, Renaud Goullioud, P. O. Lagage, J. M. LeDuigou, Alain Delboulbé, Christophe Cara, P. Kern, Fabien Malbet, E. Doumayrou, E. Behar, M. Saint-Pe, Olivier Preis, Bijan Nemati, J. Dupont, S. Rochat, Guillermo Martin, Philippe Feautrier, S. Lafrasse, Chengxing Zhai, S. Potin, and Antoine Crouzier
Subjects: Point spread function, Computer science, Physics::Instrumentation and Detectors, FOS: Physical sciences, Context (language use), 01 natural sciences, 010309 optics, Planet, 0103 physical sciences, Calibration, Computer vision, 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Signal processing, Pixel, business.industry, Detector, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, Astrometry, Interferometry, Space and Planetary Science, Artificial intelligence, Astrophysics::Earth and Planetary Astrophysics, business, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: Context: Exoplanet science has made staggering progress in the last two decades, due to the relentless exploration of new detection methods and refinement of existing ones. Yet astrometry offers a unique and untapped potential of discovery of habitable-zone low-mass planets around all the solar-like stars of the solar neighborhood. To fulfill this goal, astrometry must be paired with high precision calibration of the detector. Aims: We present a way to calibrate a detector for high accuracy astrometry. An experimental testbed combining an astrometric simulator and an interferometric calibration system is used to validate both the hardware needed for the calibration and the signal processing methods. The objective is an accuracy of 5e-6 pixel on the location of a Nyquist sampled polychromatic point spread function. Methods: The interferometric calibration system produced modulated Young fringes on the detector. The Young fringes were parametrized as products of time and space dependent functions, based on various pixel parameters. The minimization of func- tion parameters was done iteratively, until convergence was obtained, revealing the pixel information needed for the calibration of astrometric measurements. Results: The calibration system yielded the pixel positions to an accuracy estimated at 4e-4 pixel. After including the pixel position information, an astrometric accuracy of 6e-5 pixel was obtained, for a PSF motion over more than five pixels. In the static mode (small jitter motion of less than 1e-3 pixel), a photon noise limited precision of 3e-5 pixel was reached.
Published: 2016

19. NAOMI: a low-order adaptive optics system for the VLT interferometer

Author: Pavel Shchkaturov, Julien Woillez, Angela Cortes, Javier Reyes, Jean-Baptiste Le Bouquin, Norbert Hubin, Paul Jolley, Rob Donaldson, Jean-Jacques Correia, Yves Magnard, F. Delplancke-Ströbele, Marcos Suarez, Laurence Michaud, Thanh Phan Duc, Sebastian Egner, Emmanuel Aller-Carpentier, Miska Le Louarn, J. Quentin, Stefan Huber, T. Moulin, Frédéric Gonté, Luca Pasquini, Luigi Andolfato, Jaime Alonso, Guillermo Valdes, R. Ridings, Reinhold J. Dorn, Didier Maurel, Jean-Philippe Berger, Paul Lilley, Sylvain Rochat, Christophe Dupuy, Alessandro Martis, Alain Roux, Jerome Paufique, J. P. Kirchbauer, Jean-Luc Beuzit, Christophe Verinaud, Alain Delboulbé, and Eric Stadler
Subjects: Physics, Wavefront, Interferometry, Optics, 010308 nuclear & particles physics, business.industry, 0103 physical sciences, Astronomical interferometer, Strehl ratio, business, Adaptive optics, 010303 astronomy & astrophysics, 01 natural sciences
Abstract: The New Adaptive Optics Module for Interferometry (NAOMI) will be developed for and installed at the 1.8-metre Auxiliary Telescopes (ATs) at ESO Paranal. The goal of the project is to equip all four ATs with a low-order Shack– Hartmann adaptive optics system operating in the visible. By improving the wavefront quality delivered by the ATs for guide stars brighter than R = 13 mag, NAOMI will make the existing interferometer performance less dependent on the seeing conditions. Fed with higher and more stable Strehl, the fringe tracker(s) will achieve the fringe stability necessary to reach the full performance of the second-generation instruments GRAVITY and MATISSE.
Published: 2016
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20. Single Mode LiNbO3Waveguides at 4.7 μm by Proton Exchange: Addressing the Atmospheric M-Band

Author: Mercedes Carrascosa, Angel GarcÍA, Guillermo Martin, Romain Grille, Alain Delboulbé, José Olivares, Pierre Kern, and Olga Caballero-Calero
Subjects: Birefringence, Materials science, business.industry, Infrared, Lithium niobate, Single-mode optical fiber, Physics::Optics, Condensed Matter Physics, Waveguide (optics), Fourier transform spectroscopy, Electronic, Optical and Magnetic Materials, Wavelength, chemistry.chemical_compound, Optics, chemistry, business, Refractive index
Abstract: In this paper we present new infrared waveguides based on proton-exchanged Lithium Niobate samples. Characterization of the waveguides in the visible and near infrared allows to develop a wavelength dependence function for refractive index and birefringence that predicts a single mode behaviour at 4.7 μm. This was confirmed by Fourier Transform Spectroscopy and compared to beam propagation simulations. We have obtained the first single mode planar waveguide at 4.7 μm, based on a simple technique that could be interesting for developing integrated optics beam combiners for astronomy.
Published: 2009
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21. New LiNbO3Devices for Infrared Interferometry and Evanescent-Field Sensing: Integrated Single Mode Young's Slit Interferometer at 3.39 μm

Author: Alain Delboulbé, Pierre Kern, Guillermo Martin, Eric Anselm, Nadège Courjal, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174) (FEMTO-ST), Université de Technologie de Belfort-Montbeliard (UTBM)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Université de Franche-Comté (UFC), and Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, Spectrometer, Infrared, business.industry, Lithium niobate, Astrophysics::Instrumentation and Methods for Astrophysics, Single-mode optical fiber, Physics::Optics, Condensed Matter Physics, 01 natural sciences, Waveguide (optics), Electronic, Optical and Magnetic Materials, 010309 optics, Interferometry, chemistry.chemical_compound, Planar, Optics, chemistry, 0103 physical sciences, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Emission spectrum, business, 010303 astronomy & astrophysics
Abstract: International audience; We present an integrated Lithium Niobate device based on single mode behaviour of a planar waveguide at 3.39 μm, made by Titanium diffusion. After an experimental and theoretical study of the waveguide in the infrared, we present the set-up that allows an interferometric measurement of the emission spectrum and thus that can be applied as an integrated spectrometer. An integrated device such as presented here could be part of an astronomical instrument in order to study spectral characteristics of stars or exoplanets.
Published: 2009
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22. NEAT breadboard system analysis and performance models

Author: S. Lafrasse, Alain Léger, Fabien Malbet, Alain Delboulbé, Christophe Cara, Guillermo Martin, François Hénault, Philippe Feautrier, Pierre Kern, Jean-Michel Le Duigou, Eric Staedler, and Antoine Crouzier
Subjects: Physics, Test bench, Pixel, business.industry, Astrometry, Breadboard, Exoplanet, law.invention, Metrology, Telescope, law, Aerospace engineering, business, Circumstellar habitable zone, Remote sensing
Abstract: NEAT (Nearby Earth Astrometric Telescope) is an astrometric space mission aiming at detecting Earth-like exoplanets located in the habitable zone of nearby solar-type stars. For that purpose, NEAT should be able to measure stellar centroids within an accuracy of 5 10 -6 pixels. In order to fulfil such stringent requirement, NEAT incorporates an interferometric metrology system measuring pixel gains and location errors. To validate this technology and assess the whole performance of the instrument, a dedicated test bench has been built at IPAG, in Grenoble (France). In this paper are summarized the main system engineering considerations allowing to define sub-systems specifications. Then we describe the general architecture of the performance models (including photometric, interferometric, and final astrometric budgets) and confront their predictions with the experimental results obtained on the test bench. It is concluded that most of error items are well understood, although some of them deserve further investigations.
Published: 2014
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23. First experimental results of very high accuracy centroiding measurements for the neat astrometric mission

Author: S. Lafrasse, Fabien Malbet, Guillermo Martin, J. M. LeDuigou, Pierre-Olivier Lagage, François Hénault, M. Donati, M. Saint-Pe, J. Dupont, Philippe Feautrier, Mike Shao, Renaud Goullioud, S. Potin, P. Kern, E. Behar, Olivier Preis, Antoine Crouzier, A. Léger, Eric Stadler, Alain Delboulbé, Christophe Cara, and E. Doumayrou
Subjects: Pixel, Spacecraft, Computer science, business.industry, Measure (physics), Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Astrometry, Exoplanet, Metrology, Physics::Space Physics, Astrophysics::Earth and Planetary Astrophysics, business, Astrophysics - Instrumentation and Methods for Astrophysics, Algorithm, Instrumentation and Methods for Astrophysics (astro-ph.IM)
Abstract: NEAT is an astrometric mission proposed to ESA with the objectives of detecting Earth-like exoplanets in the habitable zone of nearby solar-type stars. NEAT requires the capability to measure stellar centroids at the precision of 5e-6 pixel. Current state-of-the-art methods for centroid estimation have reached a precision of about 2e-5 pixel at two times Nyquist sampling, this was shown at the JPL by the VESTA experiment. A metrology system was used to calibrate intra and inter pixel quantum efficiency variations in order to correct pixelation errors. The European part of the NEAT consortium is building a testbed in vacuum in order to achieve 5e-6 pixel precision for the centroid estimation. The goal is to provide a proof of concept for the precision requirement of the NEAT spacecraft. In this paper we present the metrology and the pseudo stellar sources sub-systems, we present a performance model and an error budget of the experiment and we report the present status of the demonstration. Finally we also present our first results: the experiment had its first light in July 2013 and a first set of data was taken in air. The analysis of this first set of data showed that we can already measure the pixel positions with an accuracy of about 1e-4 pixel., Comment: SPIE conference proceedings
Published: 2013
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24. PIONIER: a status report

Author: Wesley A. Traub, Alain Roux, S. Rochat, T. Moulin, N. Blind, Karine Perraut, Pierre Haguenauer, P. Kern, Gerard Zins, Alain Delboulbé, Fabien Malbet, Myriam Benisty, P. Rabou, Jean-Charles Augereau, J. Knudstrup, M. Germain, Philippe Feautrier, Bernard Lazareff, Rafael Millan-Gabet, François Ménard, L. Michaud, Dan Popovic, Jean-Philippe Berger, J.-L. Lizon, F. Roussel, M. Micallef, D. Maurel, Eric Stadler, Mario Kiekebusch, Laurent Jocou, E. Tatulli, Olivier Absil, Yves Magnard, Philippe B. Gitton, J.-B. Le Bouquin, D. Gillier, Delplancke, Françoise, Rajagopal, Jayadev K., and Malbet, Fabien
Subjects: medicine.medical_specialty, Computer science, Visitor pattern, medicine, FOS: Physical sciences, Medical physics, Integrated optics, Technical committee, Astrophysics - Instrumentation and Methods for Astrophysics, Status report, Instrumentation and Methods for Astrophysics (astro-ph.IM)
Abstract: The visitor instrument PIONIER provides VLTI with improved imaging capabilities and sensitivity. The instrument started routinely delivering scientific data in November 2010, that is less than 12 months after being approved by the ESO Science and Technical Committee. We recall the challenges that had to be tackled to design, built and commission PIONIER. We summarize the typical performances and some astrophysical results obtained so far. We conclude this paper by summarizing lessons learned., Comment: To appear in the proceedings of the 2012 SPIE Conference "Astronomical Telescopes and Instrumentation"
Published: 2012

25. Two telescopes ABCD electro-optic beam combiner based on lithium niobate for near infrared stellar interferometry

Author: Alain Delboulbé, M. Gineys, Samuel Heidmann, J. P. Berger, T. Moulin, J.-B. Le Bouquin, Guillermo Martin, Laurent Jocou, A. Nolot, and O. Caballero
Subjects: Wavefront, Physics, business.industry, Lithium niobate, Optical communication, Phase (waves), Single-mode optical fiber, Physics::Optics, law.invention, Interferometry, chemistry.chemical_compound, Optics, chemistry, Achromatic lens, law, Optoelectronics, business, Group delay and phase delay
Abstract: Lithium Niobate (LN) based electro-optic modulators are well known in the optical communications field, due to their high bandwidth and deep rejection ratio [1]. These performances could be used in the field of astronomy for stellar interferometry in the mid-infrared domain [2]. With our partners from Photline Technologies, we have conceived, developed and characterized a 2T ABCD [3] beam combiner in the near-infrared (1.5μm, the H-band in astrophysics). The modulation scheme, presented below in Figure 1, allows to determine the fringe characteristics in a single shot measurement, without the need to externally scan the optical phase delay. Fine adjustment of the relative phase can be achieved using the electro-optic properties of the lithium niobate waveguides. In particular, the phase on each output can be electrically controlled and locked by using appropriate electrodes. These devices have to ensure modal filtering to reject optical aberrations of the wavefront and thus optimize the fringes contrast, which means that they have to be single mode through all the spectral range of interest. This also means that the couplers should be achromatic and balanced in order to optimize the fringe contrast. We will present results on global transmission, performance of the couplers and the electro-optic behavior of the device using monochromatic as well as wide spectral sources in the H-band.
Published: 2011
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26. PIONIER: combining 4 telescopes of the very large telescope interferometer using a photonics beam combiner

Author: Fabien Malbet, Alain Roux, W. A. Traub, Laurent Jocou, J.-L. Lizon, Gerard Zins, Sebastien Morel, Philippe B. Gitton, D. Gillier, Alain Delboulbé, Pierre Haguenauer, L. Michaud, Jean-Philippe Berger, Eric Stadler, F. Roussel, Karine Perraut, P. Kern, Sylvain Rochat, J. B. Lebouquin, M. Germain, Philippe Feautrier, D. Maurel, B. Lazareff, Pierre Labeye, Rafael Millan-Gabet, Patrick Rabou, Yves Magnard, and T. Moulin
Subjects: Physics, Very Large Telescope, business.industry, Infrared, Near-infrared spectroscopy, Astrophysics::Instrumentation and Methods for Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Interferometry, Optics, Astrophysics::Solar and Stellar Astrophysics, Integrated optics, Astrophysics::Earth and Planetary Astrophysics, Photonics, business, Image resolution, Astrophysics::Galaxy Astrophysics, Beam (structure)
Abstract: PIONIER (Precision Integrated Optics Near-infrared Imaging ExpeRiment) is a visitor instrument [1] that performs the interferometric beam combination in the near infrared of the light delivered by the 4 main telescopes (8m) or auxiliary telescopes (1.8m) of the VLTI on the ESO Paranal site (Chile).
Published: 2011
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27. FFREE: a Fresnel-FRee Experiment for EPICS, the EELT planets imager

Author: P. Rabou, Olivier Preis, Christophe Vérinaud, Jacopo Antichi, Emmanuel Aller-Carpentier, Thierry Fusco, Jean-François Sauvage, Alain Delboulbé, Sarah Dandy, Norbert Hubin, Markus Kasper, Jean-Luc Beuzit, and Gerard Zins
Subjects: Diffraction, Wavefront, Physics, business.industry, Near-infrared spectroscopy, Bandwidth (signal processing), FOS: Physical sciences, Speckle pattern, Optics, Cardinal point, Apodization, business, Adaptive optics, Optics (physics.optics), Physics - Optics
Abstract: The purpose of FFREE - the new optical bench devoted to experiments on high-contrast imaging at LAOG - consists in the validation of algorithms based on off-line calibration techniques and adaptive optics (AO) respectively for the wavefront measurement and its compensation. The aim is the rejection of the static speckles pattern arising in a focal plane after a diffraction suppression system (based on apodization or coronagraphy) by wavefront pre-compensation. To this aim, FFREE has been optimized to minimize Fresnel propagation over a large near infrared (NIR) bandwidth in a way allowing efficient rejection up to the AO control radius, it stands then as a demonstrator for the future implementation of the optics that will be common to the scientific instrumentation installed on EPICS., 12 pages, 15 figures, Proceeding 7736120 of the SPIE Conference "Adaptive Optics Systems II", monday 28 June 2010, San Diego, California, USA
Published: 2010
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28. Low voltage, moderate rejection ratio electro-optic modulator at 2.2μm obtained by proton exchange in lithium niobate

Author: Alain Delboulbé, Laurent Jocou, Jean-Philippe Berger, Guillermo Martin, Romain Burla, Olga Caballero-Calero, and T. Moulin
Subjects: White light interferometry, Materials science, business.industry, Lithium niobate, Single-mode optical fiber, Electro-optic modulator, Mach–Zehnder interferometer, chemistry.chemical_compound, Optics, chemistry, Band-pass filter, Photonics, business, Low voltage
Abstract: In this paper we present the performances of a modulator, realized by proton exchange, achieving a moderate rejection ratio in the K-band (2.2μm). The device consists on a simple Mach-Zehnder beam combiner, developed by our partners from Photline Technologies®, pushing forward their proton exchange technique in order to achieve single mode optical guiding above 1.9μm in Lithium Niobate X-cut substrates. Applying low modulation voltages (V π =3.4V), and by a Fast Fourier Transform obtain the spectrum of the source with a moderate resolution, due to the reduced length of the active part (32mm). A white light interferometer is also shown, using a band-pass filter, from 1.8 to 2.6μm.
Published: 2010
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29. System overview of the VLTI Spectro-Imager

Author: Fabien Malbet, Udo Beckmann, Philippe Feautrier, Christopher A. Haniff, Dario Lorenzetti, J.-B. Le Bouquin, A. Chelli, Mario Gai, P. Kern, Gerard Zins, Karine Perraut, José Manuel Rebordão, Leonardo Corcione, P. Rabou, Gaspard Duchêne, Olivier Absil, Gerd Weigelt, David F. Buscher, Davide Loreggia, Alain Delboulbé, E. Herwats, Jorge Lima, E. Le Coarer, Jean-Phillipe Berger, Pierre Labeye, G. Li Causi, Myriam Benisty, António Amorim, Sebastiano Ligori, John Young, Paulo J. V. Garcia, Laurent Jocou, and Gilles Duvert
Subjects: Physics, Scientific instrument, Very Large Telescope, Astrophysics (astro-ph), Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Astrophysics, Interferometry, Temporal resolution, Closure phase, Angular resolution, Spectral resolution, Spectrograph, Remote sensing
Abstract: The VLTI Spectro Imager project aims to perform imaging with a temporal resolution of 1 night and with a maximum angular resolution of 1 milliarcsecond, making best use of the Very Large Telescope Interferometer capabilities. To fulfill the scientific goals (see Garcia et. al.), the system requirements are: a) combining 4 to 6 beams; b) working in spectral bands J, H and K; c) spectral resolution from R= 100 to 12000; and d) internal fringe tracking on-axis, or off-axis when associated to the PRIMA dual-beam facility. The concept of VSI consists on 6 sub-systems: a common path distributing the light between the fringe tracker and the scientific instrument, the fringe tracker ensuring the co-phasing of the array, the scientific instrument delivering the interferometric observables and a calibration tool providing sources for internal alignment and interferometric calibrations. The two remaining sub-systems are the control system and the observation support software dedicated to the reduction of the interferometric data. This paper presents the global concept of VSI science path including the common path, the scientific instrument and the calibration tool. The scientific combination using a set of integrated optics multi-way beam combiners to provide high-stability visibility and closure phase measurements are also described. Finally we will address the performance budget of the global VSI instrument. The fringe tracker and scientific spectrograph will be shortly described.
Published: 2008

30. Single-mode LiNbO 3 -based waveguides for L-band interferometry

Author: Eric Anselm, Guillermo Martin, O. Caballero, Nadège Courjal, Laurent Jocou, Alain Delboulbé, Thibaut Seure, T. Moulin, José Olivares, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174) (FEMTO-ST), Université de Technologie de Belfort-Montbeliard (UTBM)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS), and Universidad Autonoma de Madrid (UAM)
Subjects: [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], L band, Materials science, Ion beam, business.industry, 010401 analytical chemistry, Lithium niobate, Single-mode optical fiber, Physics::Optics, 01 natural sciences, 7. Clean energy, Waveguide (optics), 0104 chemical sciences, 010309 optics, chemistry.chemical_compound, Interferometry, Optics, chemistry, 0103 physical sciences, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Astronomical interferometer, Double-slit experiment, business
Abstract: International audience; We present three different techniques for single-mode waveguide realization in Lithium Niobate at the 3.39µm atmospheric transmission band, named L-band. These methods include Titanium diffusion, Ion Beam Implantation and Photo-inscription. After describing the fabrication process and waveguide characterization, we will present an integrated interferometer based on the Young's double slit experiment. From the recorded interferogram we recover information about the source, namely, its peak emission lines.
Published: 2008
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31. Characterization of integrated optics components for the second generation of VLTI instruments

Author: Myriam Benisty, Pierre Kern, Xavier Haubois, Fabien Malbet, Karine Rousselet-Perraut, Laurent Jocou, Alain Delboulbé, Pierre Labeye, Jean-Phillipe Berger, T. Moulin, G. Perrin, Sylvestre Lacour, Emilie Herwats, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Pôle Astronomie du LESIA, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris
Subjects: Physics, Gravity (chemistry), business.industry, Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics, Characterization (materials science), Integrated optics, Instrumentation (computer programming), Aerospace engineering, business, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Beam (structure)
Abstract: Two of the three instruments proposed to ESO for the second generation instrumentation of the VLTI would use integrated optics for beam combination. Several design are studied, including co-axial and multi-axial recombination. An extensive quantity of combiners are therefore under test in our laboratories. We will present the various components, and the method used to validate and compare the different combiners. Finally, we will discuss the performances and their implication for both VSI and Gravity VLTI instruments., Comment: SPIE Astronomical Instrumentation 2008 in Marseille, France -- Equation (7) updated
Published: 2008
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32. VITRUV Precursors: IONIC2T/IONIC3T

Author: Fabien Malbet, P. Haguenauer, I. Schanen, Myriam Benisty, Markus Schöller, Laurent Jocou, J. B. Lebouquin, John D. Monnier, P. Labeye, Ettore Pedretti, Wesley A. Traub, K. Perraut, Rafael Millan-Gabet, J. P. Berger, Andreas Glindemann, Alain Delboulbé, and P. Kern
Subjects: Physics, Young stellar object, Closure phase, Astrophysics
Published: 2007
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33. Recent Progress in Mid Infrared Integrated Optics for Nulling Interferometry

Author: Laetitia Abel-Tiberini, Annie Pradel, P. Labeye, Cyril Ruilier, Volker Kirschner, Etienne LeCoarer, Alain Delboulbé, Caroline Vigreux-Bercovici, Pierre Saguet, Pierre Kern, Marc Barillot, Jean-Emmanuel Broquin, Brahim Arezki, Lucas Labadie, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Microélectronique, Electromagnétisme et Photonique (IMEP), Université Joseph Fourier - Grenoble 1 (UJF)-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS), European Space Research and Technology Centre (ESTEC), Agence Spatiale Européenne = European Space Agency (ESA), 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), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique de Grenoble (INPG)-Université Joseph Fourier - Grenoble 1 (UJF), and European Space Agency (ESA)
Subjects: Wavefront, Physics, business.industry, Optical engineering, Near-infrared spectroscopy, 02 engineering and technology, 021001 nanoscience & nanotechnology, Polarization (waves), 01 natural sciences, 7. Clean energy, Starlight, law.invention, 010309 optics, Interferometry, Modal, Optics, law, 0103 physical sciences, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], 0210 nano-technology, business, Waveguide, ComputingMilieux_MISCELLANEOUS
Abstract: This paper presents the development and tests in the thermal infrared of Integrated Optics (IO) technology in preparation of ESA's space mission Darwin . This mission aims to detect and characterize earth-like planets orbiting solar-type stars, using nulling interferometry in the spectral range 6 - 20 μm. Since typically 1:1e6 rejection of starlight is required, wavefront modal filtering is mandatory. Thus, mid-infrared single-mode IO is being developed in the framework of the ESA-funded "Integrated Optics for Darwin" project. Beyond its wavefront filtering capabilities, an IO component may support various optical functions, and is thus likely to ease instrumental design. This paper addresses the manufacturing process and the characterization tests results of newly developed IO devices. Investigated solutions are dielectric waveguides based on Chalcogenide glasses and Hollow Metallic Waveguides. In a first phase, the pre-selected technological solutions were validated and modal behavior of the manufactured devices was demonstrated, both through polarization and spectral analysis. Preliminary nulling ratios up to 5000 have been obtained with an IO modal filter in the 6 - 20 μm range. In a second phase of the project, the development of more complex IO functions was attempted. The methods used to validate the waveguide behavior and interferometric capabilities are also discussed. After achieving 1:1e5 polychromatic extinctions with similar solutions in the near IR, the presented results further underline the credibility of a mid-infrared IO concept for Darwin.© (2006) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Published: 2006
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34. Integrated optics for astronomical interferometry - VI. Coupling the light of the VLTI in K band

Author: Jean-Baptiste Le Bouquin, Karine Rousselet-Perraut, Andreas Glindemann, Laurent Jocou, Jean-Philippe Berger, P. Labeye, Alain Delboulbé, Fatemeh Zabihian, Markus Schoeller, Pierre Kern, Fabien Malbet, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), 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), and European Southern Observatory (ESO)
Subjects: Phase (waves), FOS: Physical sciences, Astrophysics, 01 natural sciences, 010309 optics, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], symbols.namesake, Optics, K band, 0103 physical sciences, optical interferometry, 010303 astronomy & astrophysics, Physics, Coupling, instrumentation, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Linear polarization, business.industry, Astrophysics (astro-ph), Single-mode optical fiber, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, Interferometry, Fourier transform, Space and Planetary Science, integrated optics, symbols, business, Beam (structure)
Abstract: Our objective is to prove that integrated optics (IO) is not only a good concept for astronomical interferometry but also a working technique with high performance. We used the commissioning data obtained with the dedicated K-band integrated optics two-telescope beam combiner which now replaces the fiber coupler MONA in the VLTI/VINCI instrument. We characterize the behaviour of this IO device and compare its properties to other single mode beam combiner like the previously used MONA fiber coupler. The IO combiner provides a high optical throughput, a contrast of 89% with a night-to-night stability of a few percent. Even if a dispersive phase is present, we show that it does not bias the measured Fourier visibility estimate. An upper limit of 0.005 for the cross-talk between linear polarization states has been measured. We take advantage of the intrinsic contrast stability to test a new astronomical prodecure for calibrating diameters of simple stars by simultaneously fitting the instrumental contrast and the apparent stellar diameters. This method reaches an accuracy with diameter errors of the order of previous ones but without the need of an already known calibrator. These results are an important step of integrated optics and paves the road to incoming imaging interferometer projects.
Published: 2006
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35. AMBER integration and laboratory performances

Author: Gerard Zins, E. Tatulli, Yves Magnard, Florentin Millour, J. Behrend, Karine Rousselet-Perraut, Matteo Accardo, P. Antonelli, Stephane Lagarde, Yves Bresson, Franco Lisi, Carla S. Gil, Fabien Malbet, Etienne LeCoarer, Udo Beckmann, S. Busoni, Pierre Kern, L. Gluck, Gilles Duvert, Alain Delboulbé, Brahim Arezki, Sylvie Robbe-Dubois, Alain Roussel, and Romain Petrov
Subjects: Physics, Accuracy and precision, Optics, Modal, business.industry, K band, media_common.quotation_subject, Contrast (vision), Spectral resolution, business, Throughput (business), Stability (probability), media_common
Abstract: AMBER is the focal near-infrared instrument of the VLTI combining 2 or 3 telescopes in the J, H and K bands with 3 spectral resolution modes. It uses single-mode fibers to ensure modal filtering and high measurement accuracies. AMBER has been integrated and tested in Grenoble during 2003. We report in this paper the lab performances of the instrument in terms of instrumental contrast, measurement accuracy and stability, and throughput.
Published: 2004
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36. The VLTI focal instrument Amber: results of the first phase of the alignment, integration, and verification in Paranal

Author: Gerd Weigelt, Florentin Millour, P. Stefanini, Martin Vannier, Gerard Zins, Franco Lisi, Andrea Richichi, Pedro Mardones, Gilles Duvert, Fredrik T. Rantakyrö, Etienne LeCoarer, Karine Rousselet-Perraut, Stephane Lagarde, Florence Puech, Markus Schoeller, Carla S. Gil, L. Gluck, P. Antonelli, N. Haddad, E. Tatulli, Fabien Malbet, Udo Beckmann, M. Heininger, Pierre Kern, Matteo Accardo, Nico Housen, Denis Mourard, Sylvie Robbe-Dubois, Romain Petrov, Mario Kiekebusch, Yves Bresson, Alain Delboulbé, and Alain Roussel
Subjects: Physics, Stars, Optics, business.industry, Instrumentation, Phase (waves), Multi beam, Spectral bands, business, Visibility, Differential phase, Remote sensing
Abstract: AMBER, Astronomical Multi BEam combineR, is the near-infrared focal instrument dedicated to the VLTI. It is designed to combine three of the VLTI Telescopes and to work simultaneously in the J, H and K spectral bands (1.0 to 2.4 μm). The project successfully passed the Preliminary Acceptance in Europe in November 2003, resulting in the validation of the instrument laboratory performance1, of the compliance with the initial scientific specifications, and of the acceptance of ESO for AMBER to be part of the VLTI. After the transportation of the instrument to Paranal, Chile in January 2004, the Assembly Integration and Verification phase occurred mid-March to succeed with the first fringes observing bright stars with the VLTI siderostats. This paper describes the different steps of the AIV and the first results in terms of instrumental stability, estimated visibility and differential phase.
Published: 2004
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37. An integrated-optics 3-way beam combiner for IOTA

Author: P. Kern, Wesley A. Traub, Nathaniel P. Carleton, Pierre Haguenauer, John D. Monnier, Sam Ragland, Karine Rousselet-Perraut, Isabelle Schanen-Duport, Alain Delboulbé, Emmanuel Laurent, Stephane Gluck, Rafael Millan-Gabet, Jean-Philippe Berger, Ettore Pedretti, Laure Lagny, E. Tatulli, Fabien Malbet, and Traub, Wesley A.
Subjects: Physics, Iota, Interferometry, Optics, business.industry, Visibility (geometry), Astronomical interferometer, Integrated optics, Infrared Optical Telescope Array, business, Beam (structure), Preliminary analysis
Abstract: We report here the first visibility and closure-phase measurements done with the IONIC instrument at the IOTA interferometer. The IONIC instrument is presented and preliminary analysis of the results discussed. Future improvements of IONIC are envisioned.
Published: 2003

38. NAOS visible wavefront sensor

Author: Philippe Feautrier, Sylvain Laurent, Pascal Puget, Alain Delboulbé, Matthieu Cochard, Gérard Rousset, Eric Stadler, Pierre Kern, Olivier Rondeaux, Jean-Louis Lizon, Reinhold J. Dorn, Norbert Hubin, Didier Rabaud, Yves Magnard, and Patrick Rabou
Subjects: Time delay and integration, Microlens, Physics, Cryostat, Wavefront, Physics::Instrumentation and Detectors, business.industry, Astrophysics::Instrumentation and Methods for Astrophysics, Wavefront sensor, Rotation, Noise (electronics), Optics, business, Adaptive optics
Abstract: This paper describes the Visible Wave Front Sensor (visible WFS) for the VLT Nasmith Adaptive Optics system (NAOS). This Shack-Hartman-based wave front sensor instrument includes within a continuous flow liquid nitrogen cryostat: (1) a low noise fast readout CCD camera controlled by the ESO new generation CCD controller FIERA. The readout noise of this system is 3 e- at 50 kilopixel/sec/port, and is only limited by the CCD intrinsic noise. FIERA proposes remotely controlled readout modes with optional binning, windowing and flexible integration time. (2) two remotely exchangeable micro-lens arrays focusing the analyzed wave front directly on the CCD sensitive surface. The wave front sensor includes also its own atmospheric dispersion compensator. Due to the continuous rotation of the NAOS adapter, the mechanical stiffness of the visible wave front sensor must be very high not to disturb the loop operation (no more than 0.1 micrometer of lenslet array displacement compared to the CCD location over a 30 degree rotation angle of the instrument). The following simulations and tests are described: (1) simulation results providing an estimation of the NAOS maximum operating magnitude, (2) camera optimization, (3) mechanical stiffness measurements.
Published: 2000
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