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1. Narrow belt of debris around the Sco-Cen star HD 141011

Author: Virginie Faramaz, Christophe Pinte, Beth Biller, Raphael Galicher, Silvano Desidera, R. Gratton, Mickael Bonnefoy, Mariangela Bonavita, C. Lazzoni, Anthony Boccaletti, Johan Olofsson, Elisabeth Matthews, Philippe Delorme, J. L. Beuzit, C. Mordasini, Julien Milli, Gael Chauvin, Jean-Charles Augereau, A-M. Lagrange, David Mouillet, François Ménard, A. Chomez, Arthur Vigan, Dino Mesa, Sasha Hinkley, 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), INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), 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), Laboratoire de l'intégration, du matériau au système (IMS), Centre National de la Recherche Scientifique (CNRS)-Institut Polytechnique de Bordeaux-Université Sciences et Technologies - Bordeaux 1, 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, 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), University of Arizona, University of Exeter, Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), Massachusetts Institute of Technology (MIT), Universität Bern [Bern], Universidad de Valparaiso [Chile], ANR-14-CE33-0018,GIPSE,Exploration des planetes géantes extrasolaires(2014), ANR-20-CE31-0012,FRAME,Détection et Caractérisation des Exoplanètes en Formation(2020), European Project: 885593,COBREX, European Project: 776403,EXOPLANET, 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, 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 Sciences et Technologies - Bordeaux 1 (UB)-Institut Polytechnique de Bordeaux-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), 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), Université de Genève = University of Geneva (UNIGE), Universität Bern [Bern] (UNIBE), Université Grenoble Alpes (UGA), National Hospital for Neurology and Neurosurgery [London, UK], and Université Sciences et Technologies - Bordeaux 1-Institut Polytechnique de Bordeaux-Centre National de la Recherche Scientifique (CNRS)
Subjects: 530 Physics, FOS: Physical sciences, Context (language use), Astrophysics, 01 natural sciences, planetary systems -stars, 0103 physical sciences, individual, 010303 astronomy & astrophysics, planetary systems, Solar and Stellar Astrophysics (astro-ph.SR), Physics, Earth and Planetary Astrophysics (astro-ph.EP), 010308 nuclear & particles physics, 520 Astronomy, James Webb Space Telescope, stars: individual: HD 141011 (HIP 77432), techniques: high angular resolution, Astronomy and Astrophysics, Planetary system, Position angle, stars: imaging, Radial velocity, Stars, Fomalhaut, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, HD 141011 (HIP 77432), Halo, techniques, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], high contrast imaging-stars, Astrophysics - Earth and Planetary Astrophysics
Abstract: We initiated a deep-imaging survey of Scorpius-Centaurus A-F stars with predicted warm inner and cold outer belts of debris reminiscent of the architecture of emblematic systems such as HR 8799. We present resolved SPHERE images of a narrow ring of debris around the F5-type star HD 141011 that was observed as part of our survey in 2015, 2016, and 2019. The ring extends up to ~1.1" (~141 au) from the star in the IRDIS and IFS data obtained in 2016 and 2019. The disk is not detected in the 2015 data which are of poorer quality. The disks is best reproduced by models of a noneccentric ring centered on the star with an inclination of $69.1\pm0.9^{\circ}$, a position angle of $-24.6 \pm 1.7^{\circ}$, and a semimajor axis of $127.5\pm3.8$ au. The combination of radial velocity and imaging data excludes brown-dwarf (M>13.6 MJup) companions coplanar with the disk from 0.1 to 0.9 au and from 20 au up to 500 au (90% probability). HD 141011 adds to the growing list of debris disks that are resolved in Sco-Cen. It is one of the faintest disks that are resolved from the ground and has a radial extent and fractional width ($\sim$12.5%) reminiscent of Fomalhaut. Its moderate inclination and large semimajor axis make it a good target for the James Webb Space Telescope and should allow a deeper search for putative companions shaping the dust distribution., 13 pages, 10 figures. Paper II of our Sco-Cen imaging survey. Accepted in A&A
Published: 2021
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2. Unveiling the β Pictoris system, coupling high contrast imaging, interferometric, and radial velocity data

Author: Christian Straubmeier, J. Hagelberg, Anne-Marie Lagrange, A. Grandjean, Frank Eisenhauer, Myriam Benisty, Silvano Desidera, R. Asensio-Torres, Anne-Lise Maire, M. Nowak, Thibaut Paumard, F. Cantalloube, Jens Kammerer, Yann Clénet, P. T. de Zeeuw, Matthew Horrobin, Karine Perraut, Eric Gendron, O. Pfuhl, L. Pueyo, Stefan Gillessen, Stefan Hippler, John Monnier, Raphael Galicher, P. Thebault, Gael Chauvin, C. Babusiaux, J. Wang, Wolfgang Brandner, L. Kreidberg, P. Léna, V. Lapeyrère, J. M. Girard, Sylvestre Lacour, G. Rodríguez-Coira, Guy Perrin, Matthew A. Kenworthy, H. Le Coroller, G. Heissel, F. Galland, V. Christiaens, P. Delorme, V. Coudé du Foresto, E. Choquet, Matthias Samland, Hervé Beust, Miriam Keppler, Odele Straub, Mickael Bonnefoy, Gilles Duvert, Andreas Eckart, Z. Wahhaj, T. Stolker, A. Zurlo, C. Paladini, F. Vincent, G. Otten, M. Janson, O. Flasseur, J.-B. Le Bouquin, A. Mérand, Felix Widmann, G. Rousset, Jinyi Shangguan, N. Meunier, Feng Gao, R. Gratton, A. Vigan, Paul Mollière, Jean-Phillipe Berger, P. Rubini, P. Kervella, T. Henning, António Amorim, T. Schmidt, Julien Woillez, Xavier Haubois, Anthony Boccaletti, Maud Langlois, Q. Kral, P. Garcia, Thomas Ott, L. Rodet, B. Charnay, R. Garcia Lopez, Reinhard Genzel, Sergio Messina, 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), 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'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), 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), Centre de Recherche Astrophysique de Lyon (CRAL), 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), Galaxies, Etoiles, Physique, Instrumentation (GEPI), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), CENTRA-SIM, IDL-Faculdade de Ciencias da Universidade de Lisboa, Departamento de Astronomía, Universidad de Chile = University of Chile [Santiago] (UCHILE), Max-Planck-Institut für Radioastronomie (MPIFR), Max Planck Institute for Extraterrestrial Physics (MPE), Max-Planck-Gesellschaft, CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire des Combustibles Uranium (LCU), Service d'Analyses, d'Elaboration, d'Expérientations et d'Examens des combustibles (SA3E), Département d'Etudes des Combustibles (DEC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Département d'Etudes des Combustibles (DEC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Physikalisches Institut [Köln], Universität zu Köln = University of Cologne, Max-Planck-Institut für Astronomie (MPIA), University of Freiburg [Freiburg], Space Telescope Science Institute (STSci), German Research Centre for Geosciences - Helmholtz-Centre Potsdam (GFZ), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), the GRAVITY Collaboration, 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), 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), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), 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 d'Immunologie de Marseille - Luminy (CIML), Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Observatoire de Paris - Site de Paris (OP), Universität zu Köln, 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), Institut de Recherche pour le Développement (IRD), and Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)
Subjects: planets and satellites: detection, media_common.quotation_subject, Context (language use), Astrophysics, 01 natural sciences, Planet, radial velocities -planets and satellites, 0103 physical sciences, techniques: radial velocities, Astrophysics::Solar and Stellar Astrophysics, Eccentricity (behavior), 10. No inequality, planets and satellites: fundamental parameters, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, media_common, Orbital elements, Physics, [PHYS]Physics [physics], detectionplanets and satellites, 010308 nuclear & particles physics, high angular resolution -techniques, Giant planet, techniques: high angular resolution, Astronomy and Astrophysics, Astrometry, Planetary system, Radial velocity, 13. Climate action, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], techniques, fundamental parameters
Abstract: Context. The nearby and young β Pictoris system hosts a well resolved disk, a directly imaged massive giant planet orbiting at ≃9 au, as well as an inner planet orbiting at ≃2.7 au, which was recently detected through radial velocity (RV). As such, it offers several unique opportunities for detailed studies of planetary system formation and early evolution. Aims. We aim to further constrain the orbital and physical properties of β Pictoris b and c using a combination of high contrast imaging, long base-line interferometry, and RV data. We also predict the closest approaches or the transit times of both planets, and we constrain the presence of additional planets in the system. Methods. We obtained six additional epochs of SPHERE data, six additional epochs of GRAVITY data, and five additional epochs of RV data. We combined these various types of data in a single Markov-chain Monte Carlo analysis to constrain the orbital parameters and masses of the two planets simultaneously. The analysis takes into account the gravitational influence of both planets on the star and hence their relative astrometry. Secondly, we used the RV and high contrast imaging data to derive the probabilities of presence of additional planets throughout the disk, and we tested the impact of absolute astrometry. Results. The orbital properties of both planets are constrained with a semi-major axis of 9.8 ± 0.4 au and 2.7 ± 0.02 au for b and c, respectively, and eccentricities of 0.09 ± 0.1 and 0.27 ± 0.07, assuming the HIPPARCOS distance. We note that despite these low fitting error bars, the eccentricity of β Pictoris c might still be over-estimated. If no prior is provided on the mass of β Pictoris b, we obtain a very low value that is inconsistent with what is derived from brightness-mass models. When we set an evolutionary model motivated prior to the mass of β Pictoris b, we find a solution in the 10–11 MJup range. Conversely, β Pictoris c’s mass is well constrained, at 7.8 ± 0.4 MJup, assuming both planets are on coplanar orbits. These values depend on the assumptions on the distance of the β Pictoris system. The absolute astrometry HIPPARCOS-Gaia data are consistent with the solutions presented here at the 2σ level, but these solutions are fully driven by the relative astrometry plus RV data. Finally, we derive unprecedented limits on the presence of additional planets in the disk. We can now exclude the presence of planets that are more massive than about 2.5 MJup closer than 3 au, and more massive than 3.5 MJup between 3 and 7.5 au. Beyond 7.5 au, we exclude the presence of planets that are more massive than 1–2 MJup. Conclusions. Combining relative astrometry and RVs allows one to precisely constrain the orbital parameters of both planets and to give lower limits to potential additional planets throughout the disk. The mass of β Pictoris c is also well constrained, while additional RV data with appropriate observing strategies are required to properly constrain the mass of β Pictoris b.
Published: 2020
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3. Increasing the raw contrast of VLT/SPHERE with the dark hole technique

Author: Julien Milli, Elsa Huby, Anthony Boccaletti, Mamadou N'Diaye, Jean-François Sauvage, Axel Potier, Pierre Baudoz, Arthur Vigan, Zahed Wahhaj, Raphael Galicher, 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)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), 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), 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), DOTA, ONERA, Université Paris Saclay [Châtillon], ONERA-Université Paris-Saclay, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), 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), 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: media_common.quotation_subject, FOS: Physical sciences, Context (language use), Astrophysics, instrumentation: adaptive optics, 01 natural sciences, law.invention, Telescope, Optics, law, instrumentation: high angular resolution, 0103 physical sciences, Adaptive optics, 010303 astronomy & astrophysics, Coronagraph, Instrumentation and Methods for Astrophysics (astro-ph.IM), media_common, Wavefront, Physics, 010308 nuclear & particles physics, business.industry, Plane (geometry), Astrophysics::Instrumentation and Methods for Astrophysics, techniques: high angular resolution, Astronomy and Astrophysics, Exoplanet, Space and Planetary Science, Sky, Astrophysics::Earth and Planetary Astrophysics, business, Astrophysics - Instrumentation and Methods for Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: Context. Since 1995 and the first discovery of an exoplanet orbiting a main-sequence star, 4000 exoplanets have been discovered using several techniques. However, only a few of these exoplanets were detected through direct imaging. Indeed, the imaging of circumstellar environments requires high-contrast imaging facilities and accurate control of wavefront aberrations. Ground-based planet imagers such as VLT/SPHERE or Gemini/GPI have already demonstrated great performance. However, their limit of detection is hampered by suboptimal correction of aberrations unseen by adaptive optics (AO). Aims. Instead of focusing on the phase minimization of the pupil plane as in standard AO, we aim to directly minimize the stellar residual light in the SPHERE science camera behind the coronagraph to improve the contrast as close as possible to the inner working angle. Methods. We propose a dark hole (DH) strategy optimized for SPHERE. We used a numerical simulation to predict the global improvement of such a strategy on the overall performance of the instrument for different AO capabilities and particularly in the context of a SPHERE upgrade. Then, we tested our algorithm on the internal source with the AO in closed loop. Results. We demonstrate that our DH strategy can correct for aberrations of phase and amplitude. Moreover, this approach has the ability to strongly reduce the diffraction pattern induced by the telescope pupil and the coronagraph, unlike methods operating at the pupil plane. Our strategy enables us to reach a contrast of 5e-7 at 150 mas from the optical axis in a few minutes using the SPHERE internal source. This experiment establishes the grounds for implementing the algorithm on sky in the near future., Comment: Accepted for publication in Astronomy & Astrophysics
Published: 2020
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4. Comparing focal plane wavefront control techniques:\\Numerical simulations and laboratory experiments

Author: Pierre Baudoz, Raphael Galicher, Garima Singh, Anthony Boccaletti, Axel Potier, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and 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)
Subjects: planets and satellites: detection, Phase (waves), FOS: Physical sciences, Context (language use), Astrophysics, instrumentation: adaptive optics, 01 natural sciences, 7. Clean energy, Deformable mirror, 010309 optics, Speckle pattern, Optics, instrumentation: high angular resolution, 0103 physical sciences, 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Wavefront, Physics, planets and satellites: atmospheres, [PHYS]Physics [physics], business.industry, Astronomy and Astrophysics, Spectral bands, Cardinal point, 13. Climate action, Space and Planetary Science, Modulation, business, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: Fewer than 1% of all exoplanets detected to date have been characterized on the basis of spectroscopic observations of their atmosphere. Unlike indirect methods, high-contrast imaging offers access to atmospheric signatures by separating the light of a faint off-axis source from that of its parent star. Forthcoming space facilities, such as WFIRST/LUVOIR/HabEX, are expected to use coronagraphic instruments capable of imaging and spectroscopy in order to understand the physical properties of remote worlds. The primary technological challenge that drives the design of these instruments involves the precision control of wavefront phase and amplitude errors. Several FPWS and control techniques have been proposed and demonstrated in laboratory to achieve the required accuracy. However, these techniques have never been tested and compared under the same laboratory conditions. This paper compares two of these techniques in a closed loop in visible light: the pair-wise (PW) associated with electric field conjugation (EFC) and self-coherent camera (SCC). We first ran numerical simulations to optimize PW wavefront sensing and to predict the performance of a coronagraphic instrument with PW associated to EFC wavefront control, assuming modeling errors for both PW and EFC. Then we implemented the techniques on a laboratory testbed. We introduced known aberrations into the system and compared the wavefront sensing using both PW and SCC. The speckle intensity in the coronagraphic image was then minimized using PW+EFC and SCC independently. We demonstrate that both SCC and PW+EFC can generate a dark hole in space-like conditions in a few iterations. Both techniques reach the current limitation of our laboratory bench and provide coronagraphic contrast levels of 5e-9 in a narrow spectral band (, 12 pages, 11 figures. Accepted for publication in section 13. Astronomical instrumentation of A&A
Published: 2020
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5. Active minimization of non-common path aberrations in long-exposure imaging of exoplanetary systems

Author: Simone Thijs, Olivier Dupuis, Manuel Ortiz, Garima Singh, Axel Potier, Raphael Galicher, Elsa Huby, Pierre Baudoz, 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), and 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)
Subjects: media_common.quotation_subject, FOS: Physical sciences, Context (language use), Astrophysics, Residual, instrumentation: adaptive optics, 01 natural sciences, 010309 optics, Speckle pattern, Optics, 0103 physical sciences, Contrast (vision), Adaptive optics, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, media_common, Earth and Planetary Astrophysics (astro-ph.EP), [PHYS]Physics [physics], Physics, business.industry, techniques: high angular resolution, Astronomy and Astrophysics, Exoplanet, 13. Climate action, Space and Planetary Science, Instrumentation: high angular resolution, A priori and a posteriori, Halo, business, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract: Context. Spectroscopy of exoplanets is very challenging because of the high star-planet contrast. A technical difficulty in the design of imaging instruments is the noncommon path aberrations (NCPAs) between the adaptive optics (AO) sensing and the science camera, which induce planet-resembling stellar speckles in the coronagraphic science images. In an observing sequence of several long exposures, quickly evolving NCPAs average out and leave behind an AO halo that adds photon noise to the planet detection. Static NCPA can be calibrated a posteriori using differential imaging techniques. However, NCPAs that evolve during the observing sequence do not average out and cannot be calibrated a posteriori. These quasi-static NCPAs are one of the main limitations of the current direct imaging instruments such as SPHERE, GPI, and SCExAO. Aims. Our aim is to actively minimize the quasi-static speckles induced in long-exposure images. To do so, we need to measure the quasi-static speckle field above the AO halo. Methods. The self-coherent camera (SCC) is a proven technique which measures the speckle complex field in the coronagraphic science images. It is routinely used on the THD2 bench to reach contrast levels of, Comment: 10 pages, 11 figures, accepted for publication to A&A
Published: 2019
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6. Fast Coherent Differential Imaging on Ground-based Telescopes Using the Self-coherent Camera

Author: Raphael Galicher, Christian Marois, Benjamin L. Gerard, University of Victoria [Canada] (UVIC), 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), and 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)
Subjects: FOS: Physical sciences, Residual, 01 natural sciences, law.invention, 010309 optics, Speckle pattern, Optics, law, 0103 physical sciences, Sensitivity (control systems), Adaptive optics, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, Coronagraph, ComputingMilieux_MISCELLANEOUS, Earth and Planetary Astrophysics (astro-ph.EP), Physics, Wavefront, [PHYS]Physics [physics], business.industry, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, Wavefront sensor, Exoplanet, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, business, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Earth and Planetary Astrophysics
Abstract: Direct imaging and spectral characterization of exoplanets using extreme adaptive optics (ExAO) is a key science goal of future extremely large telescopes and space observatories. However, quasi-static wavefront errors will limit the sensitivity of this endeavor. Additional limitations for ground-based telescopes arise from residual AO-corrected atmospheric wavefront errors, generating millisecond-lifetime speckles that average into a halo over a long exposure. A solution to both of these problems is to use the science camera of an ExAO system as a wavefront sensor to perform a fast measurement and correction method to minimize these aberrations as soon as they are detected. We develop the framework for one such method based on the self-coherent camera (SCC) to be applied to ground-based telescopes, called Fast Atmospheric SCC Technique (FAST). We show that with the use of a specially designed coronagraph and coherent differential imaging algorithm, recording images every few milliseconds allows for a subtraction of atmospheric and static speckles while maintaining a close to unity algorithmic exoplanet throughput. Detailed simulations reach a contrast close to the photon noise limit after 30 seconds for a 1 % bandpass in H band on both 0$^\text{th}$ and 5$^\text{th}$ magnitude stars. For the 5th magnitude case, this is about 110 times better in raw contrast than what is currently achieved from ExAO instruments if we extrapolate for an hour of observing time, illustrating that sensitivity improvement from this method could play an essential role in the future detection and characterization of lower mass exoplanets.
Published: 2018
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7. Fast focal plane wavefront sensing on ground-based telescopes

Author: Benjamin L. Gerard, Jean-Pierre Véran, Raphael Galicher, and Christian Marois
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), Wavefront, Time delay and integration, business.industry, Computer science, Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Wavefront sensor, 01 natural sciences, Deformable mirror, law.invention, 010309 optics, Optics, Cardinal point, law, 0103 physical sciences, Sensitivity (control systems), Astrophysics - Instrumentation and Methods for Astrophysics, business, Adaptive optics, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, Coronagraph, Astrophysics - Earth and Planetary Astrophysics
Abstract: Exoplanet detection and characterization through extreme adaptive optics (ExAO) is a key science goal of future extremely large telescopes. This achievement, however, will be limited in sensitivity by both quasi-static wavefront errors and residual AO-corrected atmospheric wavefront errors. A solution to both of these problems is to use the science camera of an ExAO system as a wavefront sensor to perform a fast measurement and correction method to remove these aberrations as soon as they are detected. We have developed the framework for one such method, using the self-coherent camera (SCC), to be applied to ground-based telescopes, called Fast Atmospheric SCC Technique (FAST; Gerard et al., submitted). Our FAST solution requires an optimally designed coronagraph (the SCC FPM) and post-processing algorithm and is in principle able to reach a "raw" contrast of a few times the photon noise limit, continually improving with integration time. In this paper, we present new ongoing work in exploring the manufacturing limitations of the SCC FPM as well as a general framework to implement and optimize a FAST deformable mirror control loop.
Published: 2018
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8. Experimental validation of joint phase and amplitude wave-front sensing with coronagraphic phase diversity for high-contrast imaging

Author: Laurent M. Mugnier, Raphael Galicher, B. Paul, Olivier Herscovici-Schiller, Jean-François Sauvage, Pierre Baudoz, ONERA - The French Aerospace Lab [Châtillon], ONERA-Université Paris Saclay (COmUE), 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), 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), ONERA, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and 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)
Subjects: IMAGE PROCESSING, Phase (waves), Measure (physics), FOS: Physical sciences, Context (language use), Astrophysics, 01 natural sciences, Space exploration, 010309 optics, Speckle pattern, Optics, 0103 physical sciences, FOS: Electrical engineering, electronic engineering, information engineering, INSTRUMENTATION, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Wavefront, Physics, ADAPTIVE OPTICS, TECHNIQUE, business.industry, ANALYSE DE SURFACE D’ONDE, Image and Video Processing (eess.IV), Astrophysics::Instrumentation and Methods for Astrophysics, HIGH ANGULAR RESOLUTION, Astronomy and Astrophysics, CORONOGRAPHIE, Electrical Engineering and Systems Science - Image and Video Processing, Exoplanet, [PHYS.PHYS.PHYS-SPACE-PH]Physics [physics]/Physics [physics]/Space Physics [physics.space-ph], Amplitude, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, business, Astrophysics - Instrumentation and Methods for Astrophysics, Physics - Optics, Optics (physics.optics)
Abstract: Context. The next generation of space-borne instruments dedicated to the direct detection of exoplanets requires unprecedented levels of wavefront control precision. Coronagraphic wavefront sensing techniques for these instruments must measure both the phase and amplitude of the optical aberrations using the scientific camera as a wavefront sensor. Aims. In this paper, we develop an extension of coronagraphic phase diversity to the estimation of the complex electric field, that is, the joint estimation of phase and amplitude. Methods. We introduced the formalism for complex coronagraphic phase diversity. We have demonstrated experimentally on the Tr\`es Haute Dynamique testbed at the Observatoire de Paris that it is possible to reconstruct phase and amplitude aberrations with a subnanometric precision using coronagraphic phase diversity. Finally, we have performed the first comparison between the complex wavefront estimated using coronagraphic phase diversity (which relies on time-modulation of the speckle pattern) and the one reconstructed by the self-coherent camera (which relies on the spatial modulation of the speckle pattern). Results. We demonstrate that coronagraphic phase diversity retrieves complex wavefront with subnanometric precision with a good agreement with the reconstruction performed using the self-coherent camera. Conclusions. This result paves the way to coronagraphic phase diversity as a coronagraphic wave-front sensor candidate for very high contrast space missions., Comment: Reproduced with permission from Astronomy & Astrophysics, Copyright ESO
Published: 2018
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9. Status and performance of the THD2 bench in multi-deformable mirror configuration

Author: Fabien Patru, Raphael Galicher, Pierre Baudoz, Olivier Dupuis, and Simone Thijs
Subjects: Wavefront, Physics, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, FOS: Physical sciences, Exoplanet, Deformable mirror, law.invention, Telescope, Spitzer Space Telescope, Planet, law, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, Adaptive optics, Coronagraph, Instrumentation and Methods for Astrophysics (astro-ph.IM), Astrophysics::Galaxy Astrophysics
Abstract: The architecture of exoplanetary systems is relatively well known inward to 1 AU thanks to indirect techniques, which have allowed characterization of thousands of exoplanet orbits, masses and sometimes radii. The next step is the characterization of exoplanet atmospheres at long period, which requires direct imaging capability. While the characterization of a handful of young giant planets is feasible with dedicated instruments like SPHERE/VLT, GPI/Gemini, SCExAO/Subaru and soon with the coronagraphic capabilities aboard JWST, the spectroscopic study of mature giant planets and lower mass planets (Neptune-like, Super Earths) requires the achievement of better coronagraphic performance. While space-based coronagraph on WFIRST-AFTA might start this study at low spectroscopic resolution, dedicated projects on large space telescope and on the ELT will be required for a more complete spectroscopic study of these faint planets. To prepare these future instruments, we developed a high contrast imaging bench called THD, then THD2 for the upgraded version using multi-DM configuration. The THD2 bench is designed to test and compare coronagraphs as well as focal plane wavefront sensors and wavefront control techniques. It can simulate the beam provided by a space telescope and soon the first stage of adaptive optics behind a ground-based telescope. In this article, we describe in details the THD2 bench and give the results of a recent comparison study of the chromatic behavior for several coronagraph on the THD2., Comment: 9 pages, 5 figures, 1 Table, AO4ELT 2017 conference proceeding
Published: 2018
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10. Speckle correction in polychromatic light with the self-coherent camera for the direct detection of exoplanets

Author: Gérard Rousset, Pierre Baudoz, Raphael Galicher, Johan Mazoyer, 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), Haute résolution angulaire en astrophysique, 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)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, 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: Wavefront, Physics, business.industry, Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Deformable mirror, Exoplanet, law.invention, Speckle pattern, Optics, Cardinal point, law, Astrophysics::Earth and Planetary Astrophysics, business, Adaptive optics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Instrumentation and Methods for Astrophysics, Coronagraph, Instrumentation and Methods for Astrophysics (astro-ph.IM), Coherence (physics)
Abstract: Direct detection is a very promising field in exoplanet science. It allows the detection of companions with large separation and allows their spectral analysis. A few planets have already been detected and are under spectral analysis. But the full spectral characterization of smaller and colder planets requires higher contrast levels over large spectral bandwidths. Coronagraphs can be used to reach these contrasts, but their efficiency is limited by wavefront aberrations. These deformations induce speckles, star lights leaks, in the focal plane after the coronagraph. The wavefront aberrations should be estimated directly in the science image to avoid usual limitations by differential aberrations in classical adaptive optics. In this context, we introduce the Self- Coherent Camera (SCC). The SCC uses the coherence of the star light to produce a spatial modulation of the speckles in the focal plane and estimate the associated electric complex field. Controlling the wavefront with a deformable mirror, high contrasts have already been reached in monochromatic light with this technique. The performance of the current version of the SCC is limited when widening the spectral bandwidth. We will present a theoretical analysis of these issues and their possible solution. Finally, we will present test bench performance in polychromatic light., Proceedings of the SPIE, Volume 8864, id. 88640N 9 pp. (2013)
Published: 2017
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11. Experimental parametric study of the self-coherent camera

Author: Marion Mas, Gérard Rousset, Johan Mazoyer, Pierre Baudoz, Raphael Galicher, 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), Haute résolution angulaire en astrophysique, 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)-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), and National Research Council of Canada (NRC)
Subjects: Physics, Wavefront, Lyot stop, business.industry, Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Exoplanet, Deformable mirror, law.invention, Optics, Cardinal point, Spitzer Space Telescope, law, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], business, Coronagraph, Instrumentation and Methods for Astrophysics (astro-ph.IM), Coherence (physics)
Abstract: Direct imaging of exoplanets requires the detection of very faint objects orbiting close to very bright stars. In this context, the SPICES mission was proposed to the European Space Agency for planet characterization at visible wavelength. SPICES is a 1.5m space telescope which uses a coronagraph to strongly attenuate the central source. However, small optical aberrations, which appear even in space telescopes, dramatically decrease coronagraph performance. To reduce these aberrations, we want to estimate, directly on the coronagraphic image, the electric field, and, with the help of a deformable mirror, correct the wavefront upstream of the coronagraph. We propose an instrument, the Self-Coherent Camera (SCC) for this purpose. By adding a small "reference hole" into the Lyot stop, located after the coronagraph, we can produce interferences in the focal plane, using the coherence of the stellar light. We developed algorithms to decode the information contained in these Fizeau fringes and retrieve an estimation of the field in the focal plane. After briefly recalling the SCC principle, we will present the results of a study, based on both experiment and numerical simulation, analyzing the impact of the size of the reference hole., Comment: Space Telescopes and Instrumentation 2012: Optical, Infrared, and Millimeter Wave. Proceedings of the SPIE, Volume 8442, article id. 844250, 10 pp. (2012)
Published: 2017
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12. Belt(s) of debris resolved around the Sco-Cen star HIP 67497

Author: Gael Chauvin, Jean-Charles Augereau, Julien Milli, A-M. Lagrange, Anthony Boccaletti, Christophe Pinte, David Mouillet, Hervé Beust, J. L. Beuzit, Raphael Galicher, Mickael Bonnefoy, Raffaele Gratton, Arthur Vigan, Silvano Desidera, François Ménard, Philippe Delorme, C. Lazzoni, G. van der Plas, Erosion torrentielle neige et avalanches (UR ETGR (ETNA)), Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), European Southern Observatory (ESO), IRD, 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'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), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Laboratoire de l'intégration, du matériau au système (IMS), Université Sciences et Technologies - Bordeaux 1-Institut Polytechnique de Bordeaux-Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Institut 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 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), Universidad de Chile = University of Chile [Santiago] (UCHILE), PNP, PNPS, Labex OSUG, Millennium Science Initiative : RC130007, Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT) - CONICYT FONDECYT : 3140393, ANR-14-CE33-0018,GIPSE,Exploration des planetes géantes extrasolaires(2014), 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, European Southern Observatory, INAF-Osservatorio Astronomico di Padova, Universidad de Chile, and 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)
Subjects: FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Star (graph theory), 01 natural sciences, Integral field spectrograph, Planet, 0103 physical sciences, stars: individual: HIP 67497, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, planetary systems, ComputingMilieux_MISCELLANEOUS, Astrophysics::Galaxy Astrophysics, Earth and Planetary Astrophysics (astro-ph.EP), Physics, [PHYS]Physics [physics], 010308 nuclear & particles physics, Order (ring theory), techniques: high angular resolution, Astronomy and Astrophysics, Position angle, Debris, Stars, Space and Planetary Science, Halo, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Earth and Planetary Astrophysics
Abstract: In 2015, we initiated a survey of Scorpius-Centaurus A-F stars that are predicted to host warm-inner and cold-outer belts of debris similar to the case of the system HR~8799. The survey aims to resolve the disks and detect planets responsible for the disk morphology. In this paper, we study the F-type star HIP~67497 and present a first-order modelisation of the disk in order to derive its main properties. We used the near-infrared integral field spectrograph (IFS) and dual-band imager IRDIS of VLT/SPHERE to obtain angular-differential imaging observations of the circumstellar environnement of HIP~67497. We removed the stellar halo with PCA and TLOCI algorithms. We modeled the disk emission with the GRaTeR code. We resolve a ring-like structure that extends up to $\sim$450 mas ($\sim$50 au) from the star in the IRDIS and IFS data. It is best reproduced by models of a non-eccentric ring with an inclination of $80\pm1^{\circ}$, a position angle of $-93\pm1^{\circ}$, and a semi-major axis of $59\pm3$ au. We also detect an additional, but fainter, arc-like structure with a larger extension (0.65 arcsec) South of the ring that we model as a second belt of debris at $\sim$130 au. We detect 10 candidate companions at separations $\geq$1''. We estimate the mass of putative perturbers responsible for the disk morphology and compare it to our detection limits. Additional data are needed to find those perturbers, and to relate our images to large-scale structures seen with HST/STIS., 6 pages, 10 figures, 4 tables. 3 appendixes. Accepted for publication in A&A
Published: 2016
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13. Astrometric Monitoring of the Hr 8799 Planets: Orbit Constraints from Self-Consistent Measurements

Author: Bruce Macintosh, Quinn Konopacky, Barry Zuckerman, Raphael Galicher, Stanimir Metchev, Christian Marois, Travis Barman, 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, 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)
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), Physics, 010504 meteorology & atmospheric sciences, FOS: Physical sciences, Astronomy, Astronomy and Astrophysics, Astrometry, Self consistent, Planetary system, 01 natural sciences, 13. Climate action, Space and Planetary Science, Planet, 0103 physical sciences, Astrophysics::Earth and Planetary Astrophysics, Orbit (control theory), National laboratory, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, Astrophysics - Earth and Planetary Astrophysics, 0105 earth and related environmental sciences
Abstract: We present new astrometric measurements from our ongoing monitoring campaign of the HR 8799 directly imaged planetary system. These new data points were obtained with NIRC2 on the W.M. Keck II 10 meter telescope between 2009 and 2014. In addition, we present updated astrometry from previously published observations in 2007 and 2008. All data were reduced using the SOSIE algorithm, which accounts for systematic biases present in previously published observations. This allows us to construct a self-consistent data set derived entirely from NIRC2 data alone. From this dataset, we detect acceleration for two of the planets (HR 8799b and e) at $>$3$\sigma$. We also assess possible orbital parameters for each of the four planets independently. We find no statistically significant difference in the allowed inclinations of the planets. Fitting the astrometry while forcing coplanarity also returns $\chi^2$ consistent to within 1$\sigma$ of the best fit values, suggesting that if inclination offsets of $\lesssim$20$^{o}$ are present, they are not detectable with current data. Our orbital fits also favor low eccentricities, consistent with predictions from dynamical modeling. We also find period distributions consistent to within 1$\sigma$ with a 1:2:4:8 resonance between all planets. This analysis demonstrates the importance of minimizing astrometric systematics when fitting for solutions to highly undersampled orbits., Comment: 18 pages, 11 figures. Accepted for publication in AJ
Published: 2016
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14. SPICES: spectro-polarimetric imaging and characterization of exoplanetary systems

Author: John T. Trauger, Jean-Charles Augereau, Naoshi Murakami, Pierre Baudoz, Raphael Galicher, Mark C. Wyatt, Pierre-Olivier Lagage, Olivier Guyon, Anne-Lise Maire, Raffaele Gratton, Daphne Stam, Anthony Boccaletti, Dimitri Mawet, Spices team, Motohide Tamura, Samuel Ronayette, Christophe Verinaud, Michiel Min, Kerri Cahoy, Didier Dubreuil, Frans Snik, Jennifer Patience, W. A. Traub, Eric Pantin, Michiel Rodenhuis, Dino Mesa, Marc J. Kuchner, Jean-Michel Reess, Ruslan Belikov, Ingrid Mary Beerer, and Jean Schneider
Subjects: Physics, Solar System, Zodiacal light, 010504 meteorology & atmospheric sciences, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, 7. Clean energy, 01 natural sciences, Exoplanet, law.invention, Jupiter, Telescope, Stars, 13. Climate action, Space and Planetary Science, Planet, law, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Spectral resolution, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences
Abstract: SPICES (Spectro-Polarimetric Imaging and Characterization of Exoplanetary Systems) is a five-year M-class mission proposed to ESA Cosmic Vision. Its purpose is to image and characterize long-period extrasolar planets and circumstellar disks in the visible (450 - 900 nm) at a spectral resolution of about 40 using both spectroscopy and polarimetry. By 2020/22, present and near-term instruments will have found several tens of planets that SPICES will be able to observe and study in detail. Equipped with a 1.5 m telescope, SPICES can preferentially access exoplanets located at several AUs (0.5-10 AU) from nearby stars ($
Published: 2012
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15. The SPHERE view of the planet-forming disk around HD 100546

Author: Thomas Henning, Francois Menard, Andreas Bazzon, Antonio Garufi, Henning Avenhaus, E. Sissa, Markus Kasper, Anthony K. Cheetham, Gijs D. Mulders, Markus Janson, Raffaele Gratton, Jean-Charles Augereau, Francois Wildi, Graeme Salter, Anne-Lise Maire, Dino Mesa, Anne-Marie Lagrange, Tomas Stolker, Esther Buenzli, Carsten Dominik, Wolfgang Brandner, Markus Feldt, Myriam Benisty, Silvano Desidera, Maud Langlois, Clément Perrot, Gael Chauvin, David Mouillet, Bruno Lopez, Sascha P. Quanz, Anthony Boccaletti, Christian Ginski, Arthur Vigan, Mickael Bonnefoy, Raphael Galicher, Christophe Pinte, J. Lannier, Alice Zurlo, S. Peretti, Michael Meyer, Hans Martin Schmid, M. Cudel, Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), 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), 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]), Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (... - 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), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, GDFSuez, 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, 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), ESO, Physics Department [Garching], Technische Universität Munchen - Université Technique de Munich [Munich, Allemagne] (TUM)-Technische Universität Munchen - Université Technique de Munich [Munich, Allemagne] (TUM), aucun, IDELE, University of Geneva, Genève, Low Energy Astrophysics (API, FNWI), 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), 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), 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), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-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), 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), Technical University of Munich (TUM)-Technical University of Munich (TUM), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université Nice Sophia Antipolis (1965 - 2019) (UNS), 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], and Institut de l'élevage (IDELE)
Subjects: Physics, Earth and Planetary Astrophysics (astro-ph.EP), Brightness, Photon, 010504 meteorology & atmospheric sciences, Be star, Scattering, Conjunction (astronomy), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, 01 natural sciences, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Planet, 0103 physical sciences, Astrophysics::Earth and Planetary Astrophysics, Adaptive optics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, Image resolution, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Astrophysics - Earth and Planetary Astrophysics
Abstract: We image with unprecedented spatial resolution and sensitivity disk features that could be potential signs of planet-disk interaction. Two companion candidates have been claimed in the disk around the young Herbig Ae/Be star HD100546. Thus, this object serves as an excellent target for our investigation of the natal environment of giant planets. We exploit the power of extreme adaptive optics operating in conjunction with the new high-contrast imager SPHERE to image HD100546 in scattered light. We obtain the first polarized light observations of this source in the visible (with resolution as fine as 2 AU) and new H and K band total intensity images that we analyze with the Pynpoint package. The disk shows a complex azimuthal morphology, where multiple scattering of photons most likely plays an important role. High brightness contrasts and arm-like structures are ubiquitous in the disk. A double-wing structure (partly due to ADI processing) resembles a morphology newly observed in inclined disks. Given the cavity size in the visible (11 AU), the CO emission associated to the planet candidate 'c' might arise from within the circumstellar disk. We find an extended emission in the K band at the expected location of 'b'. The surrounding large-scale region is the brightest in scattered light. There is no sign of any disk gap associated to 'b'., Accepted by A&A. 13 pages, 5 figures
Published: 2016
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16. The International Deep Planet Survey II: The frequency of directly imaged giant exoplanets with stellar mass

Author: Travis Barman, Bruce Macintosh, René Doyon, Raphael Galicher, Quinn Konopacky, Christian Marois, Barry Zuckerman, Eric L. Nielsen, Jenny Patience, David Lafrenière, and Inseok Song
Subjects: Physics, Earth and Planetary Astrophysics (astro-ph.EP), Stellar mass, 010308 nuclear & particles physics, Giant planet, Astronomy, FOS: Physical sciences, Astronomy and Astrophysics, Orbital period, 01 natural sciences, Exoplanet, Radial velocity, Stars, 13. Climate action, Space and Planetary Science, Planet, 0103 physical sciences, Binary star, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract: Radial velocity and transit methods are effective for the study of short orbital period exoplanets but they hardly probe objects at large separations for which direct imaging can be used. We carried out the international deep planet survey of 292 young nearby stars to search for giant exoplanets and determine their frequency. We developed a pipeline for a uniform processing of all the data that we have recorded with NIRC2/Keck II, NIRI/Gemini North, NICI/Gemini South, and NACO/VLT for 14 years. The pipeline first applies cosmetic corrections and then reduces the speckle intensity to enhance the contrast in the images. The main result of the international deep planet survey is the discovery of the HR 8799 exoplanets. We also detected 59 visual multiple systems including 16 new binary stars and 2 new triple stellar systems, as well as 2,279 point-like sources. We used Monte Carlo simulations and the Bayesian theorem to determine that 1.05[+2.80-0.70]% of stars harbor at least one giant planet between 0.5 and 14M_J and between 20 and 300 AU. This result is obtained assuming uniform distributions of planet masses and semi-major axes. If we consider power law distributions as measured for close-in planets instead, the derived frequency is 2.30[+5.95-1.55]%, recalling the strong impact of assumptions on Monte Carlo output distributions. We also find no evidence that the derived frequency depends on the mass of the hosting star, whereas it does for close-in planets. The international deep planet survey provides a database of confirmed background sources that may be useful for other exoplanet direct imaging surveys. It also puts new constraints on the number of stars with at least one giant planet reducing by a factor of two the frequencies derived by almost all previous works., Comment: 83 pages, 13 figures, 15 Tables, accepted in A&A
Published: 2016
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17. Exoplanet Imaging with a Phase‐induced Amplitude Apodization Coronagraph. III. Diffraction Effects and Coronagraph Design

Author: Raphael Galicher, Eugene Pluzhnik, Robert A. Woodruff, Frantz Martinache, Stephen T. Ridgway, Celia Blain, and Olivier Guyon
Subjects: Physics, Diffraction, business.industry, Phase (waves), Astronomy and Astrophysics, Exoplanet, law.invention, Telescope, Optics, Apodization, Space and Planetary Science, law, Angular resolution, business, Coronagraph, Throughput (business)
Abstract: Properly apodized pupils can deliver point-spread functions (PSFs) free of Airy rings and are suitable for high dynamical range imaging of extrasolar terrestrial planets (ETPs). To reach this goal, classical pupil apodization (CPA) unfortunately requires most of the light gathered by the telescope to be absorbed, resulting in poor throughput and low angular resolution. Phase-induced amplitude apodization (PIAA) of the telescope pupil combines the advantages of classical pupil apodization (particularly low sensitivity to low-order aberrations) with full throughput, no loss of angular resolution and little chromaticity, which makes it, theoretically, an extremely attractive coronagraph for direct imaging of ETPs. The two most challenging aspects of this technique are (1) the difficulty of polishing the required optics shapes and (2) diffraction propagation effects, which, because of their chromaticity, can decrease the spectral bandwidth of the coronagraph. We show that a properly designed hybrid system combining classical apodization with the PIAA technique can solve both problems simultaneously. For such a system, the optics shapes can be well within today's optics manufacturing capabilities, and the 10-10 PSF contrast at ≈1.5λ/D required for efficient imaging of ETPs can be maintained over the whole visible spectrum. This updated design of the PIAA coronagraph maintains the high performance of the earlier design, since only a small part of the light is lost in the classical apodizer(s).
Published: 2006
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18. Exoplanet Imaging with a Phase‐induced Amplitude Apodization Coronograph. II. Performance

Author: Raphael Galicher, Eugene Pluzhnik, Stephen T. Ridgway, Frantz Martinache, and Olivier Guyon
Subjects: Physics, business.industry, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, Planetary system, Exoplanet, law.invention, Telescope, Optics, Apodization, Space and Planetary Science, Planet, law, Astrophysics::Solar and Stellar Astrophysics, Terrestrial planet, Angular resolution, Astrophysics::Earth and Planetary Astrophysics, business, Coronagraph
Abstract: The phase-induced amplitude apodization coronagraph (PIAAC) uses a lossless achromatic apodization of the telescope pupil to produce a coronagraphic image without compromising the throughput and angular resolution of the telescope. Whereas the principle of the PIAAC concept was discussed in a previous paper, the purpose of this work is to provide an exhaustive analysis of the expected performances of a PIAAC on a 4 m diameter telescope in space. Results presented here are based on realistic simulations of extrasolar terrestrial planets (ETPs) orbiting F, G, K, and M stars within 30 pc of the solar system and take into account the probability distributions of planet phase and angular separation. We show that a quasi-complete detection survey of 100 stars (with six observations per star) would require about 2 days of "open shutter" observing time in the ideal system considered in this work (4 m telescope, 100% throughput). A classical apodizer would require exposure times about 100 times longer than PIAAC on a Sun-Earth system at 10 pc. Small pointing errors and non-monochromatic observing require slight oversizing of the focal plane mask with little impact on the system performance.
Published: 2006
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19. The Phase Induced Amplitude Apodization Coronagraph: an overview of simulations and laboratory effort

Author: Raphael Galicher, Eugene Pluzhnik, Celia Blain, Frantz Martinache, Robert A. Woodruff, Olivier Guyon, Stephen T. Ridgway, 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: Wavefront, Physics, business.industry, Angular distance, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, Exoplanet, law.invention, Optics, Apodization, Space and Planetary Science, Planet, law, Angular diameter, Angular resolution, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], business, Coronagraph
Abstract: The high contrast (typically $10^{10}$ ) and small angular separation between a planet and its parent star are the main challenges that need to be overcome to detect and characterize Earth-like planets around the nearest stars. Therefore, exoplanet imaging requires the use of a coronagraph, that ideally efficiently cancels the light from the star and has minimal influence on the planet image. The Phase Induced Amplitude Apodization Coronagraph relies on pupil apodization by geometrical remapping of the flux in the pupil plane. This method combines the advantages of classical pupil apodization with high throughput ( $\approx$ 100%) and high angular resolution ( ${\approx}\lambda/D$ ), and has some unique advantages over most coronagraphs, such as low chromaticity, low sensitivity to stellar angular size and to small pointing errors. As a result, planet detection time is about 50–100 times shorter in comparison with classical coronagraphic techniques (Martinache et al. 2005). Both the advantages of the PIAAC and the main factors affecting the performance of the coronograph will be examined in our laboratory experiment in which high quality PIAA optics wilkl be combined with wavefront control to demonstrate achromatic high contrast imaging ( $10^6$ or more) at small angular separation (less than $2\lambda/D$ ). We present here a description and current status of this experiment together with a short analyses of the main factors affecting the performance of the coronograph.
Published: 2005
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20. The Phase-Induced Amplitude Coronagraph (PIAA)

Author: Celia Blain, Olivier Guyon, Stephen T. Ridgway, Robert A. Woodruff, Frantz Martinache, Raphael Galicher, Eugene Pluzhnik, 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, business.industry, Phase (waves), Astronomy, Astronomy and Astrophysics, Planetary system, law.invention, Amplitude, Optics, Space and Planetary Science, law, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], business, Coronagraph
Abstract: International audience
Published: 2005
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21. A Self-consistent Cloud Model for Brown Dwarfs and Young Giant Exoplanets: Comparison with Photometric and Spectroscopic Observations

Author: M. Bonnefoy, Raphael Galicher, Bruno Bézard, Anthony Boccaletti, Jean-Loup Baudino, Benjamin Charnay, 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), University of Oxford [Oxford], Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Université 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), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), and Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])
Subjects: 010504 meteorology & atmospheric sciences, Continuum (design consultancy), Brown dwarf, FOS: Physical sciences, Astrophysics, 01 natural sciences, Photometry (optics), 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Earth and Planetary Astrophysics (astro-ph.EP), [PHYS]Physics [physics], Physics, Photosphere, Microphysics, Condensation, Astronomy and Astrophysics, Exoplanet, 13. Climate action, Space and Planetary Science, Magnitude (astronomy), Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Earth and Planetary Astrophysics
Abstract: We developed a simple, physical and self-consistent cloud model for brown dwarfs and young giant exoplanets. We compared different parametrisations for the cloud particle size, by either fixing particle radii, or fixing the mixing efficiency (parameter fsed) or estimating particle radii from simple microphysics. The cloud scheme with simple microphysics appears as the best parametrisation by successfully reproducing the observed photometry and spectra of brown dwarfs and young giant exoplanets. In particular, it reproduces the L-T transition, due to the condensation of silicate and iron clouds below the visible/near-IR photosphere. It also reproduces the reddening observed for low-gravity objects, due to an increase of cloud optical depth for low gravity. In addition, we found that the cloud greenhouse effect shifts chemical equilibriums, increasing the abundances of species stable at high temperature. This effect should significantly contribute to the strong variation of methane abundance at the L-T transition and to the methane depletion observed on young exoplanets. Finally, we predict the existence of a continuum of brown dwarfs and exoplanets for absolute J magnitude=15-18 and J-K color=0-3, due to the evolution of the L-T transition with gravity. This self-consistent model therefore provides a general framework to understand the effects of clouds and appears well-suited for atmospheric retrievals., 24 pages, 20 figures, submitted to ApJ. Comments welcome
Published: 2018
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22. Atmospheric Characterization of Cold Exoplanets Using a 1.5-m Space Coronagraph

Author: Pierre Baudoz, Anne-Lise Maire, Daphne Stam, Wesley A. Traub, Kerri Cahoy, Raphael Galicher, Jean Schneider, Anthony Boccaletti, 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), Haute résolution angulaire en astrophysique, 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)-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), National Research Council of Canada (NRC), Laboratoire Univers et Théories (LUTH (UMR_8102)), Department of Earth Atmospheric and Planetary Sciences, MIT, SRON Netherlands Institute for Space Research (SRON), Jet Propulsion Laboratory, California Institute of Technology (JPL), and Haghighipour, Nader
Subjects: Physics, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, Planetary system, Space (mathematics), Exoplanet, law.invention, Astrobiology, Characterization (materials science), Space and Planetary Science, law, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Coronagraph
Abstract: We present numerical results of the science performance of the SPICES mission, which aims to characterize the spectro-polarimetric properties of cold exoplanets and circumstellar disks in the visible. We focus on the instrument ability to retrieve the spectral signatures of molecular species, clouds and surface of super-Earths in the habitable zone of solar-type stars. Considering realistic reflected planet spectra and instrument limitation, we show that SPICES could analyse the atmosphere and surface of a few super-Earths within 5 pc of the Sun.
Published: 2012
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23. A narrow, edge-on disk resolved around HD 106906 with SPHERE

Author: Matthias Samland, Thomas Henning, Lyu Abe, S. Peretti, Anne-Lise Maire, Hervé Beust, H. Le Coroller, F. Madec, Clément Perrot, Raphael Galicher, Johan Olofsson, Gael Chauvin, Mickael Bonnefoy, Christian Thalmann, Cyril Petit, A-M. Lagrange, Maud Langlois, Markus Janson, Dino Mesa, Graeme Salter, E. Sissa, Julien Girard, J. L. Beuzit, L. Weber, Wolfgang Brandner, Raffaele Gratton, Matthew A. Kenworthy, Julien Milli, J. Lannier, Silvano Desidera, François Ménard, Markus Feldt, D. Perret, C. Soenke, Anthony Boccaletti, P. Rabou, David Mouillet, Esther Buenzli, Vanessa P. Bailey, Anthony Cheetham, Arthur Vigan, Zahed Wahhaj, Surace, Christian, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Centre 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), 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), INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Steward Observatory, University of Arizona, 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), Centre scientifique et Technique Jean Feger (CSTJF), TOTAL FINA ELF, Sterrewacht Leiden, Universiteit Leiden [Leiden], Institute for Astronomy [Zürich], Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Geneva Observatory, Université de Genève = University of Geneva (UNIGE), Department of Astronomy, Stockholm University, Observatoire de Haute-Provence (OHP), Institut Pythéas (OSU PYTHEAS), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS), 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), De la Molécule aux Nanos-objets : Réactivité, Interactions et Spectroscopies (MONARIS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), ESO, Physics Department [Garching], Technische Universität Munchen - Université Technique de Munich [Munich, Allemagne] (TUM)-Technische Universität Munchen - Université Technique de Munich [Munich, Allemagne] (TUM), European Synchrotron Radiation Facility (ESRF), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet - Saint-Étienne (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble [2011-2019] (IPAG [2011-2019]), Observatoire des Sciences de l'Univers de Grenoble [1985-2015] (OSUG [1985-2015]), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology [2007-2019] (Grenoble INP [2007-2019])-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology [2007-2019] (Grenoble INP [2007-2019])-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), 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), Instituto de Fisica y Astronomia, ICM nucleus on protoplanetary disks, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), 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, 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), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut de Recherche pour le Développement (IRD), 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)-Centre National de la Recherche Scientifique (CNRS), ONERA - The French Aerospace Lab [Châtillon], Université Paris Saclay (COmUE)-ONERA, Université Joseph Fourier - Grenoble 1 (UJF), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), TOTAL-Scientific and Technical Center Jean Féger (CSTJF), University of Geneva [Switzerland], 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), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Technical University of Munich (TUM)-Technical University of Munich (TUM), Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble [1985-2015] (OSUG [1985-2015]), Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology [2007-2019] (Grenoble INP [2007-2019])-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology [2007-2019] (Grenoble INP [2007-2019])-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES), Centre National de la Recherche Scientifique (CNRS)-Universidad de Concepción [Chile]-Pontificia Universidad Católica de Chile (UC)-Universidad de Chile-Institut national des sciences de l'Univers (INSU - CNRS), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Universiteit Leiden, Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Jean Monnet - Saint-Étienne (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), 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, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA), ONERA, and université J.Fourier
Subjects: Brightness, 010504 meteorology & atmospheric sciences, HD 106906, FOS: Physical sciences, Astrophysics, 01 natural sciences, [SDU] Sciences of the Universe [physics], Planet, 0103 physical sciences, PLANETARY SYSTEMS, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), 0105 earth and related environmental sciences, Physics, Earth and Planetary Astrophysics (astro-ph.EP), Debris disk, Spectrometer, Plane (geometry), HIGH ANGULAR RESOLUTION, Astronomy and Astrophysics, Planetary system, [PHYS.PHYS.PHYS-SPACE-PH]Physics [physics]/Physics [physics]/Space Physics [physics.space-ph], Orbit, Astrophysics - Solar and Stellar Astrophysics, Radiation pressure, 13. Climate action, Space and Planetary Science, [SDU]Sciences of the Universe [physics], [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR] Physics [physics]/Astrophysics [astro-ph], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Earth and Planetary Astrophysics
Abstract: HD~106906AB is so far the only young binary system around which a planet has been imaged and a debris disk evidenced thanks to a strong IR excess. As such, it represents a unique opportunity to study the dynamics of young planetary systems. We aim at further investigating the close (tens of au scales) environment of the HD~106906AB system. We used the extreme AO fed, high contrast imager SPHERE recently installed on the VLT to observe HD~106906. Both the IRDIS imager and the Integral Field Spectrometer were used. We discovered a very inclined, ring-like disk at a distance of 65~au from the star. The disk shows a strong brightness asymmetry with respect to its semi-major axis. It shows a smooth outer edge, compatible with ejection of small grains by the stellar radiation pressure. We show furthermore that the planet's projected position is significantly above the disk's PA. Given the determined disk inclination, it is not excluded though that the planet could still orbit within the disk plane if at a large separation (2000--3000 au). We identified several additional point sources in the SPHERE/IRDIS field-of-view, that appear to be background objects. We compare this system with other debris disks sharing similarities, and we briefly discuss the present results in the framework of dynamical evolution., Comment: 7 pages, 6 figures, accepted by Astronomy & Astrophysics
Published: 2015
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24. GPI PSF subtraction with TLOCI: the next evolution in exoplanet/disk high-contrast imaging

Author: Thayne Currie, Raphael Galicher, Christian Marois, Rob De Rosa, Carlos Correia, Bruce Macintosh, and Patrick Ingraham
Subjects: High contrast imaging, Reference image, Infrared, Computer science, Integral Field Unit, media_common.quotation_subject, ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, FOS: Physical sciences, Rotated images, 01 natural sciences, Noise (electronics), 010309 optics, Optimized combinations, Planet, 0103 physical sciences, Contrast (vision), Image subtraction, Gemini Planet Imager, Computer vision, Adaptive optics, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, media_common, Earth and Planetary Astrophysics (astro-ph.EP), Signal to noise ratio, business.industry, Astrophysics::Instrumentation and Methods for Astrophysics, Subtraction, Polychromatic images, Circumstellar disk, Stars, Exoplanet, Extrasolar planets, Optical transfer function, Sky, Circumstellar disks, Astrophysics::Earth and Planetary Astrophysics, Artificial intelligence, Astrophysics - Instrumentation and Methods for Astrophysics, business, Algorithms, Astrophysics - Earth and Planetary Astrophysics
Abstract: To directly image exoplanets and faint circumstellar disks, the noisy stellar halo must be suppressed to a high level. To achieve this feat, the angular differential imaging observing technique and the least-squares Locally Optimized Combination of Images (LOCI) algorithm have now become the standard in single band direct imaging observations and data reduction. With the development and commissioning of new high-order high-contrast adaptive optics equipped with integral field units, the image subtraction algorithm needs to be modified to allow the optimal use of polychromatic images, field-rotated images and archival data. A new algorithm, TLOCI (for Template LOCI), is designed to achieve this task by maximizing a companion signal-to-noise ratio instead of simply minimizing the noise as in the original LOCI algorithm. The TLOCI technique uses an input spectrum and template Point Spread Functions (PSFs, generated from unocculted and unsaturated stellar images) to optimize the reference image least-squares coefficients to minimize the planet self-subtraction, thus maximizing its throughput per wavelength, while simultaneously providing a maximum suppression of the speckle noise. The new algorithm has been developed using on-sky GPI data and has achieved impressive contrast. This paper presents the TLOCI algorithm, on-sky performance, and will discuss the challenges in recovering the planet spectrum with high fidelity., Adaptive Optics Systems IV, June 22-27, 2014, Series: Proceedings of SPIE; no. 9148
Published: 2014
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25. S4EI (Spectral Sampling with Slicer for Stellar and Extragalactical Instrumentation), a new-generation of 3D spectro-imager dedicated to night astronomy

Author: Frédéric Sayède, Pierre Mein, Jean-Marie Malherbe, Mathieu Puech, Jean-Philippe Amans, G. Fasola, Raphael Galicher, Piercarlo Bonifacio, Galaxies, Etoiles, Physique, Instrumentation (GEPI), 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 instrumental, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), 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, Physique solaire, 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, business.industry, media_common.quotation_subject, Astrophysics::Instrumentation and Methods for Astrophysics, Holography, Astronomy, Extragalactic astronomy, Field of view, Astrophysics::Cosmology and Extragalactic Astrophysics, Exoplanet, law.invention, Interstellar medium, Optics, Sky, law, Astrophysics::Earth and Planetary Astrophysics, Emission spectrum, Spectral resolution, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], business, Astrophysics::Galaxy Astrophysics, media_common
Abstract: Multichannel Subtractive Double Pass (MSDP) spectrographs have been widely used in solar spectroscopy because of their ability to provide an excellent compromise between field of view and spatial and spectral resolutions. Compared with other types of spectrographs, MSDP can deliver simultaneous monochromatic images at higher spatial and spectral resolutions without any time-scanning requirement (as with Fabry-Perot spectrographs), and with limited loss of flux. These performances are obtained thanks to a double pass through the dispersive element. Recent advances with VPH (Volume phase holographic) Grisms as well as with image slicers now make MSDP potentially sensitive to much smaller fluxes. We present S4EI (Spectral Sampling with Slicer for Stellar and Extragalactical Instrumentation), which is a new concept for extending MSDP to night-time astronomy. It is based on new generation reflecting plane image slicers working with large apertures specific to night-time telescopes. The resulting design could be potentially very attractive and innovative for different domains of astronomy, e.g., the simultaneous spatial mapping of accurately flux-calibrated emission lines between OH sky lines in extragalactic astronomy or the simultaneous imaging of stars, exoplanets and interstellar medium. We present different possible MSDP/S4EI configurations for these science cases and expected performances on telescopes such as the VLT.
Published: 2014
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26. The high contrast imaging modes of MICADO

Author: Anthony Boccaletti, Michael Hartl, Raphael Galicher, Damien Gratadour, Tristan Buey, Eric Gendron, Richard Davies, Pierre Baudoz, Sylvestre Lacour, Gérard Rousset, Yann Clénet, 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), Haute résolution angulaire en astrophysique, 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)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, 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: Physics, business.industry, Near-infrared spectroscopy, High contrast imaging, Exoplanet, law.invention, Telescope, Optics, law, Extremely Large Telescope, Detection performance, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Adaptive optics, business, Coronagraph
Abstract: We present in this paper an overview of the high contrast imaging modes of the wide-field imager MICADO. MICADO is a near-IR camera for the European Extremely Large Telescope (E-ELT), featuring a wide field (75”), spectroscopic and coronagraphic capabilities. It has been chosen by ESO as one of the two first-light instruments. MICADO will be optimized for the multi-conjugate adaptive optics module MAORY and will also work in SCAO mode. This SCAO mode will provide MICADO with a high-level, on-axis correction, making use of the M4 adaptive mirror in the telescope. After presenting the scientific interest for high contrast imaging modes in MICADO, we describe the technical choices we are studying. We present the hypotheses chosen for our simulation tools and contrast as well as planet detection performance derived from this tool.
Published: 2014
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27. Near-infrared detection and characterization of the exoplanet HD 95086 b with the Gemini Planet Imager

Author: Thayne Currie, Mickael Bonnefoy, J. Rameau, Raphael Galicher, Jean-Loup Baudino, Anthony Boccaletti, Christian Marois, Gael Chauvin, A-M. Lagrange, 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), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG ), Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), University of Oxford [Oxford], Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), and University of Oxford
Subjects: stars, photometry, FOS: Physical sciences, Astrophysics, instrumentation: adaptive optics, Photometry (optics), evolutionary models, satellites, planets, Planet, Gemini Planet Imager, stars: individual, Solar and Stellar Astrophysics (astro-ph.SR), ComputingMilieux_MISCELLANEOUS, Physics, planets and satellites: atmospheres, Earth and Planetary Astrophysics (astro-ph.EP), [PHYS]Physics [physics], Atmospheric models, Near-infrared spectroscopy, Astronomy and Astrophysics, color magnitude diagrams, initial conditions, Exoplanet, color, Baryon, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, Spectral energy distribution, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], planets and satellites: detections, spectral energy distribution, Astrophysics - Earth and Planetary Astrophysics
Abstract: HD 95086 is an intermediate-mass debris-disk-bearing star. VLT/NaCo $3.8 \mu m$ observations revealed it hosts a $5\pm2 \mathrm{M}_{Jup}$ companion (HD 95086 b) at $\simeq 56$ AU. Follow-up observations at 1.66 and 2.18 $\mu m$ yielded a null detection, suggesting extremely red colors for the planet and the need for deeper direct-imaging data. In this Letter, we report H- ($1.7 \mu m$) and $\mathrm{K}_1$- ($2.05 \mu m$) band detections of HD 95086 b from Gemini Planet Imager (GPI) commissioning observations taken by the GPI team. The planet position in both spectral channels is consistent with the NaCo measurements and we confirm it to be comoving. Our photometry yields colors of H-L'= $3.6\pm 1.0$ mag and K$_1$-L'=$2.4\pm 0.7$ mag, consistent with previously reported 5-$\sigma$ upper limits in H and Ks. The photometry of HD 95086 b best matches that of 2M 1207 b and HR 8799 cde. Comparing its spectral energy distribution with the BT-SETTL and LESIA planet atmospheric models yields T$_{\mathrm{eff}}\sim$600-1500 K and log g$\sim$2.1-4.5. Hot-start evolutionary models yield M=$5\pm2$ M$_{Jup}$. Warm-start models reproduce the combined absolute fluxes of the object for M=4-14 M$_{Jup}$ for a wide range of plausible initial conditions (S$_{init}$=8-13 k$_{B}$/baryon). The color-magnitude diagram location of HD 95086 b and its estimated T$_{\mathrm{eff}}$ and log g suggest that the planet is a peculiar L-T transition object with an enhanced amount of photospheric dust., Comment: 4 pages, 4 figures, 3 tables, accepted on April, 15th, 2014
Published: 2014
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28. High-contrast imaging with a self-coherent camera

Author: Raphael Galicher, Gérard Rousset, Pierre Baudoz, Johan Mazoyer, 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), Haute résolution angulaire en astrophysique, 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)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, 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: Physics, business.industry, Deformable mirror, law.invention, Speckle pattern, Optics, Achromatic lens, law, A priori and a posteriori, Contrast ratio, Computer vision, Monochromatic color, Artificial intelligence, business, Adaptive optics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Coronagraph
Abstract: Direct imaging of exoplanets is very challenging because the planet is 104 to 1010 fainter than the star at a separation of a fraction of arcsec. Several coronagraphs have been proposed to reduce the contrast ratio but their performance strongly depends on the level of phase and amplitude aberrations that induce speckles in the science image. An active control of the aberrations and a posteriori calibration are thus required to reach very high contrasts. Classical adaptive optics are not sufficient for this purpose because of non-common path aberrations. Our team proposed a self-coherent camera that spatially modulates the speckles in the science image. It is then possible to both actively control a deformable mirror and calibrate the residuals a posteriori. The current paper is an overview of the developments we have been working on for 7 years. We present the principle of the self-coherent camera, laboratory performance obtained in monochromatic light, and upgrades of the technique to make it achromatic.
Published: 2013

29. FOMALHAUT b: INDEPENDENT ANALYSIS OF THE HUBBLE SPACE TELESCOPE PUBLIC ARCHIVE DATA

Author: Barry Zuckerman, Christian Marois, Raphael Galicher, Bruce Macintosh, 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), University of Victoria [Canada] (UVIC), Kavli Institute for Particle Astrophysics and Cosmology (KIPAC), and Stanford University
Subjects: 010504 meteorology & atmospheric sciences, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Planet, Hubble space telescope, 0103 physical sciences, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Physics, Earth and Planetary Astrophysics (astro-ph.EP), [PHYS]Physics [physics], Near-infrared spectroscopy, Astronomy, Astronomy and Astrophysics, Astrometry, Orbit, Wavelength, Fomalhaut, Space and Planetary Science, Spectral energy distribution, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Earth and Planetary Astrophysics
Abstract: The nature and even the existence of a putative planet-mass companion ("Fomalhaut b") to Fomalhaut has been debated since 2008. In the present paper we reanalyze the multi-epoch ACS/STIS/WFC3 Hubble Space Telescope (HST) optical/near infrared images on which the discovery and some other claims were based. We confirm that the HST images do reveal an object in orbit around Fomalhaut but the detailed results from our analysis differ in some ways from previous discussions. In particular, we do not confirm flux variability over a two-year interval at 0.6 microns wavelength and we detect Fomalhaut b for the first time at the short wavelength of 0.43 microns. We find that the HST image of Fomalhaut b at $0.8\,\mu$m may be extended beyond the PSF. We cannot determine from our astrometry if Fomalhaut b will cross or not the dust ring. The optical through mid-infrared spectral energy distribution (SED) of Fomalhaut b cannot be explained as due to direct or scattered radiation from a massive planet. We consider two models to explain the SED: (1) a large circumplanetary disk around an unseen planet and (2) the aftermath of a collision during the past 50-150 years of two Kuiper Belt-like objects of radii 50 km., Comment: 24 pages, 9 figures, 5 tables, accepted on April, 3rd, 2013
Published: 2013
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30. Independent confirmation of β Pictoris b imaging with NICI

Author: Mickael Bonnefoy, Anne-Marie Lagrange, Anthony Boccaletti, Raphael Galicher, Gael Chauvin, 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), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG ), Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), European Southern Observatory (ESO), Observatoire des Sciences de l'Univers de Grenoble (OSUG), and Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, [PHYS]Physics [physics], 010504 meteorology & atmospheric sciences, Gas giant, Astronomy and Astrophysics, Context (language use), Astrophysics, 01 natural sciences, Exoplanet, law.invention, Telescope, Jupiter, 13. Climate action, Space and Planetary Science, law, Planet, 0103 physical sciences, Beta Pictoris, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, Orbital separation, Astrophysics - Earth and Planetary Astrophysics, 0105 earth and related environmental sciences
Abstract: Context. {\beta} Pictoris b is one of the most studied objects nowadays since it was identified with VLT/NaCo as a bona-fide exoplanet with a mass of about 9 times that of Jupiter at an orbital separation of 8-9 AU. The link between the planet and the dusty disk is unambiguously attested and this system provides an opportunity to study the disk/planet interactions and to constrain formation and evolutionary models of gas giant planets. Still, {\beta} Pictoris b had never been confirmed with other telescopes so far. Aims. We aimed at an independent confirmation using a different instrument. Methods. We retrieved archive images from Gemini South obtained with the instrument NICI, which is designed for high contrast imaging. The observations combine coronagraphy and angular differential imaging and were obtained at three epochs in Nov. 2008, Dec. 2009 and Dec. 2010. Results. We report the detection with NICI of the planet {\beta} Pictoris b in Dec. 2010 images at a separation of 404 \pm 10 mas and P A = 212.1 \pm 0.7{\deg} . It is the first time this planet is observed with a telescope different than the VLT., Comment: Letter accepted for publication in Astronomy and Astrophysics on Feb. 21, 2013. 4 pages, 2 figures
Published: 2013
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31. Atmospheric characterization of cold exoplanets using a 1.5-m coronagraphic space telescope

Author: Kerri Cahoy, Wesley A. Traub, Pierre Baudoz, Anthony Boccaletti, Jean Schneider, Raphael Galicher, Anne-Lise Maire, Daphne Stam, 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), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), SRON Netherlands Institute for Space Research (SRON), Jet Propulsion Laboratory (JPL), and NASA-California Institute of Technology (CALTECH)
Subjects: Metallicity, FOS: Physical sciences, Context (language use), 7. Clean energy, 01 natural sciences, Jupiter, Spitzer Space Telescope, Planet, 0103 physical sciences, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Earth and Planetary Astrophysics (astro-ph.EP), Physics, [PHYS]Physics [physics], 010308 nuclear & particles physics, Astronomy, Astronomy and Astrophysics, Radius, Exoplanet, Stars, 13. Climate action, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Earth and Planetary Astrophysics
Abstract: Context. High-contrast imaging is currently the only available technique for the study of the thermodynamical and compositional properties of exoplanets in long-period orbits. The SPICES project is a coronagraphic space telescope dedicated to the spectro-polarimetric analysis of gaseous and icy giant planets as well as super-Earths at visible wavelengths. So far, studies for high-contrast imaging instruments have mainly focused on technical feasibility because of the challenging planet/star flux ratio of 10-8-10-10 required at short separations (200 mas or so) to image cold exoplanets. However, the analysis of planet atmospheric/surface properties has remained largely unexplored. Aims. The aim of this paper is to determine which planetary properties SPICES or an equivalent direct imaging mission can measure, considering realistic reflected planet spectra and instrument limitation. Methods. We use numerical simulations of the SPICES instrument concept and theoretical planet spectra to carry out this performance study. Results. We find that the characterization of the main planetary properties (identification of molecules, effect of metallicity, presence of clouds and type of surfaces) would require a median signal-to-noise ratio of at least 30. In the case of a solar-type star \leq 10 pc, SPICES will be able to study Jupiters and Neptunes up to ~5 and ~2 AU respectively. It would also analyze cloud and surface coverage of super-Earths of radius 2.5 RE at 1 AU. Finally, we determine the potential targets in terms of planet separation, radius and distance for several stellar types. For a Sun analog, we show that SPICES could characterize Jupiters (M \geq 30 ME) as small as 0.5 Jupiter radii at ~2 AU up to 10 pc, and super-Earths at 1-2 AU for the handful of stars that exist within 4-5 pc. Potentially, SPICES could perform analysis of a hypothetical Earth-size planet around alpha Cen A and B., 18 pages, 20 figures, 9 tables, accepted for publication in A&A
Published: 2012
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32. Tip-tilt estimation and correction using FQPM coronagraphic images

Author: Gérard Rousset, M. Mas, Raphael Galicher, Pierre Baudoz, 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, 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)
Subjects: 01 natural sciences, law.invention, adaptive optics, 010309 optics, Optics, law, 0103 physical sciences, Upstream (networking), Angular resolution, Adaptive optics, 010303 astronomy & astrophysics, Coronagraph, ComputingMilieux_MISCELLANEOUS, Wavefront, Physics, [PHYS]Physics [physics], business.industry, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, Wavefront sensor, image processing, Tilt (optics), Cardinal point, Space and Planetary Science, business, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], high angular resolution
Abstract: Context. Direct imaging of exoplanets located a few AU from their hosting star requires angular resolution at the diffraction limit of large telescopes and a contrast level in the image of 105 to 1010 . Simultaneous use of adaptive optics and coronagraphy is mandatory to fulfil these requirements.Aims. Coronagraphs are usually very sensitive to pointing errors upstream of their focal plane mask. Approaches to measuring these errors in conventional adaptive optics systems consist in setting a wavefront sensor in an additional channel. Differential aberrations between the coronagraphic channel and the additional one induce a loss in performance. To tackle this limitation, we propose a new technique for measuring the tip-tilt errors directly from the coronagraphic image.Methods. Our method uses the relations between the intensity distribution in the coronagraphic image and upstream tip-tilt errors. We also propose a method of estimating the tip-tilt errors downstream of the focal plane mask. We validate at visible wavelength our upstream and downstream tip-tilt estimation and compensation techniques with numerical simulation images and on laboratory images.Results. Numerical simulations predict that our techniques correct for the tip-tilt errors to a 1.3 × 10-2 λ /D level when considering a λ /40 wavefront error upstream of the coronagraph. In laboratory, where the coronagraph is mostly limited by wavefront errors, we correct for the tip-tilt errors with an accuracy better than 6.5 × 10-2 λ /D . Conclusions. We demonstrate in numerical simulations and in laboratory that our technique can efficiently estimate the tip-tilt errors directly from the coronagraphic image with no additional channel. It is robust and can be used with small wavefront errors. It should be applicable to planet imager systems currently in preparation, such as SPHERE and MIRI/JWST.
Published: 2012
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33. Third component search and abundances of the very dusty short-period binary BD +20°307

Author: Alycia J. Weinberger, Barry Zuckerman, Maria J. Cordero, Raphael Galicher, Carl Melis, and Francis C. Fekel
Subjects: Orbital elements, Physics, Component (thermodynamics), Binary number, Astronomy, Astronomy and Astrophysics, Astrophysics, Radial velocity, Stars, Space and Planetary Science, Abundance (ecology), Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Binary system, Stellar evolution, Astrophysics::Galaxy Astrophysics
Abstract: We have obtained near-infrared adaptive optics imaging and collected additional radial velocity observations to search for a third component in the extremely dusty short-period binary system BD +20°307. Our image shows no evidence for a third component at separations greater than 19AU. Our four seasons of radial velocities have a constant center-of-mass velocity and are consistent with the systemic velocities determined at two earlier epochs. Thus, the radial velocities also provide no support for a third component. Unfortunately, the separation domains covered by our imaging and radial velocity results do not overlap. Thus, we examined the parameters for possible orbits of a third component that could have been missed by our current observations. With our velocities we determined improved circular orbital elements for the 3.4 day double-lined binary. We also performed a spectroscopic abundance analysis of the short-period binary components and conclude that the stars are a mid- and a late-F dwarf. We find that the iron abundances of both components, [Fe/H] = 0.15, are somewhat greater than the solar value and comparable to that of stars in the Hyades. Despite the similarity of the binary components, the lithium abundances of the two stars are very unequal. The primary has log ε (Li) = 2.72, while in the secondary log ε (Li)≤1.46, which corresponds to a difference of at least a factor of 18. The very disparate lithium abundances in very similar stars make it impossible to ascribe a single age to them. While the system is likely at least 1Gyr old, it may well be as old as the Sun. © 2012 The American Astronomical Society. All rights reserved.
Published: 2012

34. M-band Imaging of the HR 8799 Planetary System Using an Innovative LOCI-based Background Subtraction Technique

Author: Bruce Macintosh, Quinn Konopacky, Christian Marois, Travis S. Barman, and Raphael Galicher
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), planets and satellites: atmospheres, Solar System, Background subtraction, Brown dwarf, Exoplanetology, FOS: Physical sciences, Astronomy and Astrophysics, techniques: image processing, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Planetary system, Surface gravity, methods: data analysis, Photometry (optics), Space and Planetary Science, Planet, instrumentation: high angular resolution, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, methods: observational, Astrophysics - Instrumentation and Methods for Astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), planetary systems, Astrophysics - Earth and Planetary Astrophysics
Abstract: Multi-wavelength observations/spectroscopy of exoplanetary atmospheres are the basis of the emerging exciting field of comparative exoplanetology. The HR 8799 planetary system is an ideal laboratory to study our current knowledge gap between massive field brown dwarfs and the cold 5-Gyr old Solar system planets. The HR 8799 planets have so far been imaged at J- to L-band, with only upper limits available at M-band. We present here deep high-contrast Keck II adaptive optics M-band observations that show the imaging detection of 3 of the 4 currently known HR 8799 planets. Such detections were made possible due to the development of an innovative LOCI-based background subtraction scheme that is 3 times more efficient than a classical median background subtraction for Keck II AO data, representing a gain in telescope time of up to a factor of 9. These M-band detections extend the broad band photometric coverage out to about 5 microns and provide access to the strong CO fundamental absorption band at 4.5microns. The new M-band photometry shows that the HR 8799 planets are located near the L/T-type dwarf transition, similar to what was found by other studies. We also confirm that the best atmospheric fits are consistent with low surface gravity, dusty and non-equilibrium CO/CH4 chemistry models., 10 pages, 4 figures, 1 table, accepted in ApJL
Published: 2011

35. The Self-Coherent Camera : a focal plane sensor for EPICS ?

Author: Gérard Rousset, Pierre Baudoz, Raphael Galicher, Marion Mas, 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, Wavefront, business.industry, Astrophysics::Instrumentation and Methods for Astrophysics, Wavefront sensor, Exoplanet, law.invention, Speckle pattern, Optics, Cardinal point, Planet, law, Astrophysics::Earth and Planetary Astrophysics, business, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Beam splitter, Coherence (physics)
Abstract: In the framework of the European Extremely Large Telescope, EPICS is an ambitious instrument devoted to the direct detection and the characterization of extrasolar planets. Since the performance of such an instrument is limited by wavefront errors, the use of extreme Adaptive Optic (AO) systems is mandatory. Studies for future planet finder instruments such as SPHERE/VLT or GPI/GEMINI show that a strong limitation of the performance of a planet finder is the differential aberrations that are not measured by the wavefront sensor, which is physically separated from the common optics by a beam splitter. We propose here to efficiently estimate these aberrations by directly measuring the wavefront errors in the final science image. To do so, we propose to couple the foreseen extreme AO system at high speed of EPICS with a low speed Self-Coherent Camera (SCC) which can measure directly the differential aberrations at the final science focal plane. The SCC which is based on the principle of light coherence estimates the wavefront errors by spatially encoding the speckles with fringes in the final image. After recalling the principle of the SCC, we present simulation results of the SCC performance in the context of EPICS.
Published: 2009
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36. Self-coherent camera as a focal plane wavefront sensor: simulations

Author: Pierre Baudoz, Raphael Galicher, Marion Mas, Gérard Rousset, Julien Totems, 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, 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, Groupement d'Intérêt Scientifique du Partenariat Haute résolution Angulaire Sol-Espace (GIS PHASE ), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), DOTA, ONERA, Université Paris Saclay [Palaiseau], and ONERA-Université Paris-Saclay
Subjects: Wavefront, Physics, Earth and Planetary Astrophysics (astro-ph.EP), business.industry, Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Astronomy and Astrophysics, Image processing, Wavefront sensor, Astrophysics, Deformable mirror, law.invention, Speckle pattern, Optics, Space and Planetary Science, law, High-dynamic-range imaging, Astrophysics - Instrumentation and Methods for Astrophysics, business, Adaptive optics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Coronagraph, Instrumentation and Methods for Astrophysics (astro-ph.IM), Astrophysics - Earth and Planetary Astrophysics
Abstract: Direct detection of exoplanets requires high dynamic range imaging. Coronagraphs could be the solution, but their performance in space is limited by wavefront errors (manufacturing errors on optics, temperature variations, etc.), which create quasi-static stellar speckles in the final image. Several solutions have been suggested for tackling this speckle noise. Differential imaging techniques substract a reference image to the coronagraphic residue in a post-processing imaging. Other techniques attempt to actively correct wavefront errors using a deformable mirror. In that case, wavefront aberrations have to be measured in the science image to extremely high accuracy. We propose the self-coherent camera sequentially used as a focal-plane wavefront sensor for active correction and differential imaging. For both uses, stellar speckles are spatially encoded in the science image so that differential aberrations are strongly minimized. The encoding is based on the principle of light incoherence between the hosting star and its environment. In this paper, we first discuss one intrinsic limitation of deformable mirrors. Then, several parameters of the self-coherent camera are studied in detail. We also propose an easy and robust design to associate the self-coherent camera with a coronagraph that uses a Lyot stop. Finally, we discuss the case of the association with a four-quadrant phase mask and numerically demonstrate that such a device enables the detection of Earth-like planets under realistic conditions. The parametric study of the technique lets us believe it can be implemented quite easily in future instruments dedicated to direct imaging of exoplanets., Comment: 15 pages, 14 figures, accepted in A&A (here is the final version)
Published: 2009
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37. Theory and laboratory tests of the multi-stage phase mask coronagraph

Author: Pierre Baudoz, Anthony Boccaletti, Raphael Galicher, J. Baudrand, 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, 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, Ingénieurs, Techniciens et Administratifs, Groupement d'Intérêt Scientifique du Partenariat Haute résolution Angulaire Sol-Espace (GIS PHASE ), Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)
Subjects: Physics, Phase mask, business.industry, Dephasing, Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics, law.invention, Multi stage, Optics, Planet, law, Chromatic scale, Monochromatic color, business, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Coronagraph
Abstract: A large number of coronagraphs have been proposed to overcome the ratio that exists between the star and its planet. The planet finder of the Extremely Large Telescope, which is called EPICS, will certainly need a more efficient coronagraph than the ones that have been developed so far. We propose to use a combination of chromatic Four Quadrant Phase Mask coronagraph to achromatize the dephasing of the device while maintaining a high rejection performance. After describing this multi-stage FQPM coronagraph, we show preliminary results of a study on its capabilities in the framework of the EPICS instrument, the planet finder of the European Extremely Large Telescope. Eventually, we present laboratory tests of a rough prototype of a multi-stage four-quadrant phase mask. On one hand, we deduce from our laboratory data that a detection at the 10^-10 level is feasible in monochromatic light. On the other hand, we show the detection of a laboratory companion fainter than 10^-8 with a spectral bandwidth larger than 20%., Comment: 9 pages, 9 figures, To appear in SPIE proceeding- conference 7015 held in Marseille in June 2008
Published: 2008
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38. Pupil Remapping Coronagraph (PRC): a high-performance coronagraph for a small-size visible Terrestrial Planet Finder

Author: Raphael Galicher, Robert A. Woodruff, Pierre Kern, Claude Aime, Stephen T. Ridgway, Masashi Otsubo, Rémi Soummer, Richard G. Lyon, Anne-Marie Lagrange, Daniel Rouan, Hiroshi Suto, Fabien Malbet, Anthony Boccaletti, Olivier Guyon, Motohide Tamura, Koji Murakawa, Jean-Luc Beuzit, Takayuki Kotani, 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: Diffraction, Physics, business.industry, Astronomy, Terrestrial Planet Finder, Exoplanet, law.invention, Telescope, Optics, Apodization, Planet, law, Adaptive optics, business, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Coronagraph
Abstract: Amplitude apodization of a telescope's pupil can be used to reduce the diffraction rings (Airy rings) in the PSF to allow high contrast imaging. Rather than achieving this apodization by selectively removing light at the edges of the pupil, we propose to produce the desired apodized pupil by redistributing the pupil's light. This lossless apodization concept can yield a high contrast PSF which allows the efficient detection of Earth-sized planets around stars at ~10pc with a 2m visible telescope in space. We review the current status of a JPL-funded study of this concept for the Terrestrial Planet Finder (TPF) mission, including a lab experiment and extensive computer simulations.
Published: 2004
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39. Exoplanets imaging with a Phase-Induced Amplitude Apodization Coronagraph - I. Principle

Author: Raphael Galicher, Eugene Pluzhnik, Robert A. Woodruff, Stephen T. Ridgway, Frantz Martinache, and Olivier Guyon
Subjects: Wavefront, Physics, business.industry, Astrophysics (astro-ph), Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Astronomy and Astrophysics, Field of view, Astrophysics, law.invention, Telescope, Light intensity, Optics, Apodization, Space and Planetary Science, law, Angular diameter, Angular resolution, Astrophysics::Earth and Planetary Astrophysics, business, Coronagraph
Abstract: Using 2 aspheric mirrors, it is possible to apodize a telescope beam without losing light or angular resolution: the output beam is produced by ``remapping'' the entrance beam to produce the desired light intensity distribution in a new pupil. We present the Phase-Induced Amplitude Apodization Coronagraph (PIAAC) concept, which uses this technique, and we show that it allows efficient direct imaging of extrasolar terrestrial planets with a small-size telescope in space. The suitability of the PIAAC for exoplanet imaging is due to a unique combination of achromaticity, small inner working angle (about 1.5 $\lambda/d$), high throughput, high angular resolution and large field of view. 3D geometrical raytracing is used to investigate the off-axis aberrations of PIAAC configurations, and show that a field of view of more than 100 $\lambda/d$ in radius is available thanks to the correcting optics of the PIAAC. Angular diameter of the star and tip-tilt errors can be compensated for by slightly increasing the size of the occulting mask in the focal plane, with minimal impact on the system performance. Earth-size planets at 10 pc can be detected in less than 30s with a 4m telescope. Wavefront quality requirements are similar to classical techniques., Comment: 35 pages, 16 figures, Accepted for publication in ApJ
Published: 2004
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40. Search for cool giant exoplanets around young and nearby stars

Author: Anne-Lise Maire, Pierre Baudoz, Raphael Galicher, Anthony Boccaletti, Mickael Bonnefoy, Julien Rameau, David Mouillet, Melody Sylvestre, Gael Chauvin, A.-M. Lagrange, and Silvano Desidera
Subjects: FOS: Physical sciences, Context (language use), Astrophysics, 7. Clean energy, 01 natural sciences, law.invention, law, Planet, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, Coronagraph, Earth and Planetary Astrophysics (astro-ph.EP), Physics, 010308 nuclear & particles physics, Attenuation, Near-infrared spectroscopy, Astronomy and Astrophysics, Planetary system, Exoplanet, Stars, 13. Climate action, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract: [Abridged] Context. Spectral differential imaging (SDI) is part of the observing strategy of current and future high-contrast imaging instruments. It aims to reduce the stellar speckles that prevent the detection of cool planets by using in/out methane-band images. It attenuates the signature of off-axis companions to the star, such as angular differential imaging (ADI). However, this attenuation depends on the spectral properties of the low-mass companions we are searching for. The implications of this particularity on estimating the detection limits have been poorly explored so far. Aims. We perform an imaging survey to search for cool (Teff2. According to the BT-Settl model, this translates into Teff, 19 pages, 16 figures, accepted for publication in A&A, version including language editing
Published: 2014
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41. High-contrast imaging in polychromatic light with the self-coherent camera

Author: Pierre Baudoz, Gérard Rousset, Raphael Galicher, Johan Mazoyer, 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), Technologies et systèmes d'information pour les agrosystèmes (UR TSCF), Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), 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), 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: [PHYS]Physics [physics], Wavefront, Physics, business.industry, media_common.quotation_subject, FOS: Physical sciences, Astronomy and Astrophysics, Context (language use), Astrophysics, Deformable mirror, law.invention, Speckle pattern, Optics, Cardinal point, Space and Planetary Science, law, Contrast (vision), Monochromatic color, Astrophysics - Instrumentation and Methods for Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], business, Instrumentation and Methods for Astrophysics (astro-ph.IM), Coronagraph, ComputingMilieux_MISCELLANEOUS, media_common
Abstract: Context. In the context of direct imaging of exoplanets, coronagraphs are commonly proposed to reach the required very high contrast levels. However, wavefront aberrations induce speckles in their focal plane and limit their performance. Aims. An active correction of these wavefront aberrations using a deformable mirror upstream of the coronagraph is mandatory. These aberrations need to be calibrated and focal-plane wavefront-sensing techniques in the science channel are being developed. One of these, the self-coherent camera, of which we present the latest laboratory results. Methods. We present here an enhancement of the method: we directly minimized the complex amplitude of the speckle field in the focal plane. Laboratory tests using a four-quadrant phase-mask coronagraph and a 32x32 actuator deformable mirror were conducted in monochromatic light and in polychromatic light for different bandwidths. Results. We obtain contrast levels in the focal plane in monochromatic light better than 3.10^-8 (RMS) in the 5 - 12 {\lambda}/D region for a correction of both phase and amplitude aberrations. In narrow bands (10 nm) the contrast level is 4.10^-8 (RMS) in the same region. Conclusions. The contrast level is currently limited by the amplitude aberrations on the bench. We identified several improvements that can be implemented to enhance the performance of our optical bench in monochromatic as well as in polychromatic light., Comment: 4 pages, 3 figures, accepted in Astronomy & Astrophysics (02/2014)
Published: 2014
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