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7 results on '"Marleau G"'

1. An imaged 15Mjup companion within a hierarchical quadruple system

Author

Chomez, A., Squicciarini, V., Lagrange, A. -M., Delorme, P., Viswanath, G., Janson, M., Flasseur, O., Chauvin, G., Langlois, M., Rubini, P., Bergeon, S., Albert, D., Bonnefoy, M., Desidera, S., Engler, N., Gratton, R., Henning, T., Mamajek, E. E., Marleau, G. -D., Meyer, M. R., Reffert, S., Ringqvist, S. C., and Samland, M.

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), Astrophysics - Solar and Stellar Astrophysics, FOS: Physical sciences, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics - Earth and Planetary Astrophysics
Abstract

Since 2019, the direct imaging B-star Exoplanet Abundance Study (BEAST) at SPHERE@VLT has been scanning the surroundings of young B-type stars in order to ascertain the ultimate frontiers of giant planet formation. Recently, the $17^{+3}_{-4}$ Myr HIP 81208 was found to host a close-in (~50 au) brown dwarf and a wider (~230 au) late M star around the central 2.6Msun primary. Alongside the continuation of the survey, we are undertaking a complete reanalysis of archival data aimed at improving detection performances so as to uncover additional low-mass companions. We present here a new reduction of the observations of HIP 81208 using PACO ASDI, a recent and powerful algorithm dedicated to processing high-contrast imaging datasets, as well as more classical algorithms and a dedicated PSF-subtraction approach. The combination of different techniques allowed for a reliable extraction of astrometric and photometric parameters. A previously undetected source was recovered at a short separation from the C component of the system. Proper motion analysis provided robust evidence for the gravitational bond of the object to HIP 81208 C. Orbiting C at a distance of ~20 au, this 15Mjup brown dwarf becomes the fourth object of the hierarchical HIP 81208 system. Among the several BEAST stars which are being found to host substellar companions, HIP 81208 stands out as a particularly striking system. As the first stellar binary system with substellar companions around each component ever found by direct imaging, it yields exquisite opportunities for thorough formation and dynamical follow-up studies., 12 pages, 9 figures, 5 tables. Accepted for publication as a Letter in Astronomy and Astrophysics, section 1. Letters to the Editor

Published
2023

2. Direct discovery of the inner exoplanet in the HD 206893 system : Evidence for deuterium burning in a planetary-mass companion

Author

Hinkley, S., Lacour, S., Marleau, G. -D., Lagrange, A. M., Wang, J. J., Kammerer, J., Cumming, A., Nowak, M., Rodet, L., Stolker, T., Balmer, W. -O., Ray, S., Bonnefoy, M., Mollière, P., Lazzoni, C., Kennedy, G., Mordasini, C., Abuter, R., Aigrain, S., Amorim, A., Asensio-Torres, R., Babusiaux, C., Benisty, M., Berger, J. -P., Beust, H., Blunt, S., Boccaletti, A., Bohn, A., Bonnet, H., Bourdarot, G., Brandner, W., Cantalloube, F., Caselli, P., Charnay, B., Chauvin, G., Chomez, A., Choquet, E., Christiaens, V., Clénet, Y., Foresto, V. Coudé du, Cridland, A., Delorme, P., Dembet, R., de Zeeuw, P. T., Drescher, A., Duvert, G., Eckart, A., Eisenhauer, F., Feuchtgruber, H., Galland, F., Garcia, P., Lopez, R. Garcia, Gardner, T., Gendron, E., Genzel, R., Gillessen, S., Girard, J. H., Grandjean, A., Haubois, X., Heißel, G., Henning, Th., Hippler, S., Horrobin, M., Houllé, M., Hubert, Z., Jocou, L., Keppler, M., Kervella, P., Kreidberg, L., Lapeyrère, V., Bouquin, J. -B. Le, Léna, P., Lutz, D., Maire, A. -L., Mang, F., Mérand, A., Meunier, N., Monnier, J. D., Mouillet, D., Nasedkin, E., Ott, T., Otten, G. P. P. L., Paladini, C., Paumard, T., Perraut, K., Perrin, G., Philipot, F., Pfuhl, O., Pourré, N., Pueyo, L., Rameau, J., Rickman, E., Rubini, P., Rustamkulov, Z., Samland, M., Shangguan, J., Shimizu, T., Sing, D., Straubmeier, C., Sturm, E., Tacconi, L. J., van Dishoeck, E. F., Vigan, A., Vincent, F., Ward-Duong, K., Widmann, F., Wieprecht, E., Wiezorrek, E., Woillez, J., Yazici, S., Young, A., Zicher, N., and Collaboration, the GRAVITY

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, FOS: Physical sciences, Astronomy and Astrophysics, Physik (inkl. Astronomie), Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics - Earth and Planetary Astrophysics
Abstract

Long term precise radial velocity (RV) monitoring of the nearby star HD206893, as well as anomalies in the system proper motion, have suggested the presence of an additional, inner companion in the system. Here we describe the results of a multi-epoch search for the companion responsible for this RV drift and proper motion anomaly using the VLTI/GRAVITY instrument. Utilizing information from ongoing precision RV measurements with the HARPS spectrograph, as well as Gaia host star astrometry, we report a high significance detection of the companion HD206893c over three epochs, with clear evidence for Keplerian orbital motion. Our astrometry with $\sim$50-100 $\mu$arcsec precision afforded by GRAVITY allows us to derive a dynamical mass of 12.7$^{+1.2}_{-1.0}$ M$_{\rm Jup}$ and an orbital separation of 3.53$^{+0.08}_{-0.06}$ au for HD206893c. Our fits to the orbits of both companions in the system utilize both Gaia astrometry and RVs to also provide a precise dynamical estimate of the previously uncertain mass of the B component, and therefore derive an age of $155\pm15$ Myr. We find that theoretical atmospheric/evolutionary models incorporating deuterium burning for HD206893c, parameterized by cloudy atmospheres provide a good simultaneous fit to the luminosity of both HD206893B and c. In addition to utilizing long-term RV information, this effort is an early example of a direct imaging discovery of a bona fide exoplanet that was guided in part with Gaia astrometry. Utilizing Gaia astrometry is expected to be one of the primary techniques going forward to identify and characterize additional directly imaged planets. Lastly, this discovery is another example of the power of optical interferometry to directly detect and characterize extrasolar planets where they form at ice-line orbital separations of 2-4\,au., Comment: Accepted to A&A

Published
2023

3. A scaled-up planetary system around a supernova progenitor

Author

Squicciarini, V, Gratton, R, Janson, M, Mamajek, Eric E, Chauvin, G, Delorme, P, Langlois, M, Vigan, A, Ringqvist, Simon C, Meeus, G, Reffert, S, Kenworthy, M, Meyer, M R, Bonnefoy, M, Bonavita, M, Mesa, D, Samland, M, Desidera, S, D’Orazi, V, Engler, N, Alecian, E, Miglio, A, Henning, T, Quanz, Sascha P, Mayer, L, Flasseur, O, Marleau, G-D, V. Squicciarini, R. Gratton, M. Janson, E. E. Mamajek, G. Chauvin, P. Delorme, M. Langlois, A. Vigan, S. C. Ringqvist, G. Meeus, S. Reffert, M. Kenworthy, M. R. Meyer, M. Bonnefoy, M. Bonavita, D. Mesa, M. Samland, S. Desidera, V. D'Orazi, N. Engler, E. Alecian, A. Miglio, T. Henning, S. P. Quanz, L. Mayer, O. Flasseur, G. D. Marleau, 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, 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), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique = 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), University of Zurich, and Squicciarini, V

Subjects
Astrophysics - instrumentation and methods for astrophysics, Planetary system, 530 Physics, FOS: Physical sciences, techniques: high angular resolutions, planetary system, stars: early-type, stars: individual: mu2 Scorpii, stars: individual: b Centauri, Astrophysics - solar and stellar astrophysics, 1912 Space and Planetary Science, High angular resolutions, Instrumentation and Methods for Astrophysics (astro-ph.IM), Solar and Stellar Astrophysics (astro-ph.SR), early-type, techniques: high angular resolutions [planetary systems, stars], Earth and Planetary Astrophysics (astro-ph.EP), [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astrophysics - earth and planetary astrophysics, Stars - individual - mu2 Scorpii, Astronomy and Astrophysics, Techniques, Planetary systems, [SDU]Sciences of the Universe [physics], Space and Planetary Science, 10231 Institute for Computational Science, 3103 Astronomy and Astrophysics, Stars - early-type, Stars - individual: b Centauri
Abstract

Context. Virtually all known exoplanets reside around stars with M < 2.3 M⊙ either due to the rapid evaporation of the protostellar disks or to selection effects impeding detections around more massive stellar hosts. Aims. To clarify if this dearth of planets is real or a selection effect, we launched the planet-hunting B-star Exoplanet Abundance STudy (BEAST) survey targeting B stars (M > 2.4 M⊙) in the young (5−20 Myr) Scorpius-Centaurus association by means of the high-contrast spectro-imager SPHERE at the Very Large Telescope. Methods. In this paper we present the analysis of high-contrast images of the massive (M ~ 9 M⊙) star μ2 Sco obtained within BEAST. We carefully examined the properties of this star, combining data from Gaia and from the literature, and used state-of-the-art algorithms for the reduction and analysis of our observations. Results. Based on kinematic information, we found that μ2 Sco is a member of a small group which we label Eastern Lower Scorpius within the Scorpius-Centaurus association. We were thus able to constrain its distance, refining in turn the precision on stellar parameters. Around this star we identify a robustly detected substellar companion (14.4 ± 0.8 MJ)at a projected separation of 290 ± 10 au, and a probable second similar object (18.5 ± 1.5 MJ) at 21 ± 1 au. The planet-to-star mass ratios of these objects are similar to that of Jupiter to the Sun, and the flux they receive from the star is similar to those of Jupiter and Mercury, respectively. Conclusions. The robust and the probable companions of μ2 Sco are naturally added to the giant 10.9 MJ planet recently discovered by BEAST around the binary b Cen system. While these objects are slightly more massive than the deuterium burning limit, their properties are similar to those of giant planets around less massive stars and they are better reproduced by assuming that they formed under a planet-like, rather than a star-like scenario. Irrespective of the (needed) confirmation of the inner companion, μ2 Sco is the first star that would end its life as a supernova that hosts such a system. The tentative high frequency of BEAST discoveries is unexpected, and it shows that systems with giant planets or small-mass brown dwarfs can form around B stars. When putting this finding in the context of core accretion and gravitational instability formation scenarios, we conclude that the current modeling of both mechanisms is not able to produce this kind of companion. The completion of BEAST will pave the way for the first time to an extension of these models to intermediate and massive stars., Astronomy & Astrophysics, 664, ISSN:0004-6361, ISSN:1432-0746

Published
2022
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4. SPHERE+: Imaging young Jupiters down to the snowline

Author

Augereau, J. -C., Baudino, J. -L., Beuzit, J. -L., Bouret, J. -C., Desert, J. -M., Delisle, J. -B., Orazi, V. D, Gonzalez, J. -F., Lagrange, A. -M., Coroller, H. Le, Arena, G. Muro, Diaye, M. N, Sauvage, J. -F., Schmid, H. -M., Boccaletti, A., Chauvin, G., Mouillet, D., Absil, O., Allard, F., Antoniucci, S., Augereau, J.-C, Barge, P., Baruffolo, A., Baudino, J.-L, Baudoz, P., Beaulieu, M., Benisty, M., Beuzit, J.-L, Bianco, A., Biller, B., Bonavita, B., Bonnefoy, M., Bos, S., Bouret, J.-C, Brandner, W., Buchschache, N., Carry, B., Cantalloube, F., Cascone, E., Carlotti, A., Charnay, B., Chiavassa, A., Choquet, E., Clenet, Y., Crida, A., De Boer, J., De Caprio, V., Desidera, S., Desert, J.-M, Delisle, J.-B, Delorme, P., Dohlen, K., Doelman, D., Dominik, C., D'orazi, V, Dougados, C., Douté, S., Fedele, D., Feldt, M., Ferreira, F., Fontanive, C., Fusco, T., Galicher, R., Garufi, A., Gendron, E., Ghedina, A., Ginski, C., Gonzalez, J.-F, Gratadour, D., Gratton, R., Guillot, T., Haffert, S., Hagelberg, J., Henning, T., Huby, E., Janson, M., Kamp, I., Keller, C. U., Kenworthy, M., Kervella, P., Kral, Q., Kuhn, J., Lagadec, E., Laibe, G., Langlois, M., Lagrange, A.-M, Launhardt, R., Leboulleux, L., Le Coroller, H, Causi, G. Li, Loupias, M., Maire, A. L., Marleau, G., Martinache, F., Martinez, P., Mary, D., Mattioli, M., Mazoyer, J., Meheut, H., Ménard, F., Mesa, D., Meunier, N., Miguel, Y., Milli, J., Min, M., Molliere, P., Mordasini, C., Moretto, G., Mugnier, L., Muro Arena, G, Nardetto, N., N'Diaye, M, Nesvadba, N., Pedichini, F., Pinilla, P., Por, E., Potier, A., Quanz, S., Rameau, J., Roelfsema, R., Rouan, D., Rigliaco, E., Salasnich, B., Samland, M., Sauvage, J.-F, Schmid, H.-M, Segransan, D., Snellen, I., Snik, F., Soulez, F., Stadler, E., Stam, D., Tallon, M., Thebault, P., Thiebaut, E., Tschudi, C., Udry, S., van Holstein, R., Vernazza, P, Vidal, F., Vigan, A., Waters, R., Wildi, F., Willson, M., Zanutta, A., Zavagno, Annie, Zurlo, A., 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), Leiden Observatory [Leiden], Universiteit Leiden [Leiden], 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), Observatoire de la Cte d’Azur, 96 Boulevard de l’Observatoire, Nice, 06300, France, Centre d'Etudes Lasers Intenses et Applications (CELIA), Université de Bordeaux (UB)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA), Département de Recherche sur la Fusion Contrôlée (DRFC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), 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), 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, Department of Biochemistry and Molecular Biology, Mayo Clinic, Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Physikalisches Institut [Bern], Universität Bern [Bern] (UNIBE), DOTA, ONERA, Université Paris Saclay [Châtillon], ONERA-Université Paris-Saclay, Université Côte d'Azur (UCA), University of Arizona, 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 Paris Cité (UPCité), Institute of Astronomy [ETH Zürich], Department of Physics [ETH Zürich] (D-PHYS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), NOVA Optical Infrared Instrumentation Group, INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève = University of Geneva (UNIGE), 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), SRON Netherlands Institute for Space Research (SRON), Croissance et propriétés de systèmes hybrides en couches minces (INSP-E8), Institut des Nanosciences de Paris (INSP), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), European Southern Observatory (ESO), Space Sciences, Technologies and Astrophysics Research Institute (STAR), Université de Liège, Unité de recherche d'Économie et Sociologie Rurales (ESR), Institut National de la Recherche Agronomique (INRA), INAF - Osservatorio Astronomico di Roma (OAR), Universität Greifswald - University of Greifswald, European Southern Observatory [Santiago] (ESO), Immunopathologie et chimie thérapeutique (ICT), Institut de biologie moléculaire et cellulaire (IBMC), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institute for Astronomy [Edinburgh] (IfA), University of Edinburgh, INAF - Osservatorio Astronomico di Capodimonte (OAC), Hôpital Cochin [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astrofisico di Arcetri (OAA), DOTA, ONERA, Université Paris Saclay [Palaiseau], Department of Astronomy, Stockholm University, Kapteyn Astronomical Institute [Groningen], University of Groningen [Groningen], Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Sterrewacht Leiden, Astrophysique Relativiste Théories Expériences Métrologie Instrumentation Signaux (ARTEMIS), 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 National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Observatoire de la Côte d'Azur, 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), 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)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA), 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), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Universiteit Leiden

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics - Solar and Stellar Astrophysics, [SDU]Sciences of the Universe [physics], Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Instrumentation and Methods for Astrophysics (astro-ph.IM), Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract

SPHERE (Beuzit et al,. 2019) has now been in operation at the VLT for more than 5 years, demonstrating a high level of performance. SPHERE has produced outstanding results using a variety of operating modes, primarily in the field of direct imaging of exoplanetary systems, focusing on exoplanets as point sources and circumstellar disks as extended objects. The achievements obtained thus far with SPHERE (~200 refereed publications) in different areas (exoplanets, disks, solar system, stellar physics...) have motivated a large consortium to propose an even more ambitious set of science cases, and its corresponding technical implementation in the form of an upgrade. The SPHERE+ project capitalizes on the expertise and lessons learned from SPHERE to push high contrast imaging performance to its limits on the VLT 8m-telescope. The scientific program of SPHERE+ described in this document will open a new and compelling scientific window for the upcoming decade in strong synergy with ground-based facilities (VLT/I, ELT, ALMA, and SKA) and space missions (Gaia, JWST, PLATO and WFIRST). While SPHERE has sampled the outer parts of planetary systems beyond a few tens of AU, SPHERE+ will dig into the inner regions around stars to reveal and characterize by mean of spectroscopy the giant planet population down to the snow line. Building on SPHERE's scientific heritage and resounding success, SPHERE+ will be a dedicated survey instrument which will strengthen the leadership of ESO and the European community in the very competitive field of direct imaging of exoplanetary systems. With enhanced capabilities, it will enable an even broader diversity of science cases including the study of the solar system, the birth and death of stars and the exploration of the inner regions of active galactic nuclei., White paper submitted to ESO on Feb. 20th, 2020

Published
2020

5. The influence of infall on the properties of protoplanetary discs

Author

Schib, O, Mordasini, C, Wenger, N, Marleau, G -D, Helled, R, University of Zurich, and Schib, O

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), 530 Physics, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 1912 Space and Planetary Science, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, 10231 Institute for Computational Science, 3103 Astronomy and Astrophysics, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract

We perform a population synthesis of protoplanetary discs including infall with a total of $50\,000$ simulations using a 1D vertically integrated viscous evolution code, studying a large parameter space in final stellar mass. Initial conditions and infall locations are chosen based on the results from a radiation-hydrodynamic population synthesis of circumstellar discs. We also consider a different infall prescription based on a magnetohydrodynamic (MHD) collapse simulation in order to assess the influence of magnetic fields on disc formation. The duration of the infall phase is chosen to produce a stellar mass distribution in agreement with the observationally determined stellar initial mass function. We find that protoplanetary discs are very massive early in their lives. When averaged over the entire stellar population, the discs have masses of $\sim 0.3$ and $0.1\,\mathrm{M_\odot}$ for systems based on hydrodynamic or MHD initial conditions, respectively. In systems with final stellar mass $\sim 1\,\mathrm{M_\odot}$, we find disc masses of $\sim 0.7\,\mathrm{M_\odot}$ for the `hydro' case and $\sim 0.2\,\mathrm{M_\odot}$ for the `MHD' case at the end of the infall phase. Furthermore, the inferred total disc lifetimes are long, $\approx 5-7\,\mathrm{Myr}$ on average, despite our choice of a high value of $10^{-2}$ for the background viscosity $\alpha$-parameter. In addition, fragmentation is common in systems that are simulated using hydrodynamic cloud collapse, with more fragments of larger mass formed in more massive systems. In contrast, if disc formation is limited by magnetic fields, fragmentation is suppressed entirely., Comment: 26 pages, 14 figures. Accepted to A&A

Published
2020

6. The GJ 504 system revisited. Combining interferometric, radial velocity, and high contrast imaging data

Author

Lagrange, A. -M., Marleau, G. -D., Mollière, P., Orazi, V. D, Baudino, J. -L., Bartucci, A. Musso, Elwain, M. Mc, Beuzit, J. -L., Delboulbe, A., Bonnefoy, M., Perraut, K., Lagrange, M., Delorme, P., Vigan, Arthur, Line, M., Rodet, L., Ginski, C., Mourard, D., Marleau, D., Samland, M., Tremblin, P., Ligi, R., Cantalloube, F., Molliere, P., Charnay, B., Kuzuhara, M., Janson, M., Morley, C., Homeier, D. D., D’Orazi, V., Klahr, H., Mordasini, C., Lavie, B., Baudino, L., Beust, H., Peretti, S., Musso Bartucci, A., Mesa, D., Bézard, B., Boccaletti, A., Galicher, R., Hagelberg, J., Desidera, S., Biller, B., Maire, A. -L., Allard, F., Borgniet, S., Lannier, J., Meunier, N., Desort, M., Alecian, E., Chauvin, G., Langlois, M., Henning, T., Mugnier, L., Mouillet, D., Gratton, R., Brandt, T., Mc Elwain, M., Beuzit, L., Tamura, M., Hori, Y., Brandner, W., Buenzli, E., Cheetham, A., Cudel, M., Feldt, M., Kasper, M., Keppler, M., Kopytova, T., Meyer, M., Perrot, C., Rouan, D., Salter, G., Schmidt, T., Sissa, E., Zurlo, A., Wildi, F., Blanchard, P., De Caprio, V., Delboulbé, A., Maurel, D., Moulin, T., Pavlov, A., Rabou, P., Ramos, J., Roelfsema, R., Rousset, G., Stadler, E., Rigal, François, Weber, L., 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 [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 Grenoble Alpes [2016-2019] (UGA [2016-2019])-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)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, 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 Bordelais de Recherche en Informatique (LaBRI), Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Électronique, Informatique et Radiocommunications de Bordeaux (ENSEIRB)-Université Sciences et Technologies - Bordeaux 1-Université Bordeaux Segalen - Bordeaux 2, 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), Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Laboratoire Gemini (LG), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), University of Exeter, Maison de la Simulation (MDLS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut National de Recherche en Informatique et en Automatique (Inria)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Department of Astronomy, Stockholm University, Zentrum für Astronomie der Universität Heidelberg (ZAH), Universität Heidelberg [Heidelberg], INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Physikalisches Institut [Bern], Universität Bern [Bern], Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), Department of Biochemistry and Molecular Biology, Mayo Clinic, Observatoire de Paris, Université Paris sciences et lettres (PSL), Laboratoire d'Etude des Phénomènes de Transfert Appliqués aux Bâtiments (LEPTAB), Université de La Rochelle (ULR), Centre de Recherche en Nutrition Humaine d'Auvergne (CRNH d'Auvergne), 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), ONERA - The French Aerospace Lab [Châtillon], Université Paris Saclay (COmUE)-ONERA, Riken, RIKEN - Institute of Physical and Chemical Research [Japon] (RIKEN), National Astronomical Observatory of Japan (NAOJ), Recherche Nutrition Humaine, Hôpital de l'Hôtel-Dieu de Clermont-Ferrand, Groupe d'Acoustique de l'Université de Sherbrooke (GAUS), Département de génie mécanique [Sherbrooke], Université de Sherbrooke [Sherbrooke]-Université de Sherbrooke [Sherbrooke], University of Geneva, Genève, Chimie, Ingénierie Moléculaire et Matériaux d'Angers (CIMMA), Université d'Angers (UA)-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astronomico di Capodimonte (OAC), Laboratoire d'Informatique Fondamentale et Appliquée de Tours (LIFAT), Centre National de la Recherche Scientifique (CNRS)-Université de Tours-Institut National des Sciences Appliquées - Centre Val de Loire (INSA CVL), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), NOVA Optical Infrared Instrumentation Group, European Synchrotron Radiation Facility (ESRF), 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 - 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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, School of Earth and Space Exploration, Arizona State University, P.O. 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Ejercito 441, Santiago, Chile, TNO/TPD-Space Instrumentation, and Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche en Informatique et en Automatique (Inria)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)

Subjects
010504 meteorology & atmospheric sciences, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Population, FOS: Physical sciences, Astrophysics, 01 natural sciences, Luminosity, Angular diameter, 0103 physical sciences, education, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), 0105 earth and related environmental sciences, Earth and Planetary Astrophysics (astro-ph.EP), Physics, education.field_of_study, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Mechanics of the fluids [physics.class-ph], Stellar rotation, Astronomy and Astrophysics, Radius, Surface gravity, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Radial velocity, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, Spectral energy distribution, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Earth and Planetary Astrophysics
Abstract

The G-type star GJ504A is known to host a 3 to 35 MJup companion whose temperature, mass, and projected separation all contribute to make it a test case for the planet formation theories and for atmospheric models of giant planets and light brown dwarfs. We collected data from the CHARA interferometer, SOPHIE spectrograph, and VLT/SPHERE high contrast imager to revisit the properties of the system. We measure a radius of 1.35+/- 0.04Rsun for GJ504A which yields isochronal ages of 21+/-2Myr or 4.0+/-1.8Gyr for the system and line-of-sight stellar rotation axis inclination of $162.4_{-4.3}^{+3.8}$ degrees or $18.6_{-3.8}^{+4.3}$ degrees. We re-detect the companion in the Y2, Y3, J3, H2, and K1 dual band SPHERE images. The complete 1-4 $\mu$m SED shape of GJ504b is best reproduced by T8-T9.5 objects with intermediate ages ($\leq1.5$Gyr), and/or unusual dusty atmospheres and/or super-solar metallicities. All six atmospheric models used yield $\mathrm{T_{eff}=550 \pm 50}$K for GJ504b and point toward a low surface gravity (3.5-4.0 dex). The accuracy on the metallicity value is limited by model-to-model systematics. It is not degenerate with the C/O ratio. We derive $\mathrm{log\:L/L_{\odot}=-6.15\pm0.15}$ dex for the companion compatible with masses of $\mathrm{M=1.3^{+0.6}_{-0.3}M_{Jup}}$ and $\mathrm{M=23^{+10}_{-9} M_{Jup}}$ for the young and old age ranges, respectively. The semi-major axis (sma) is above 27.8 au and the eccentricity lower than 0.55. The posterior on GJ~504b's orbital inclination suggests a misalignment with GJ~504A rotation axis. We combine the radial velocity and multi-epoch imaging data to exclude additional objects (90\% prob.) more massive than 2.5 and 30 $\mathrm{M_{Jup}}$ with sma in the range 0.01-80 au for the young and old system ages, respectively. The companion is in the envelope of the population of planets synthetized with our core-accretion model., Comment: 33 pages, 25 figures. Accepted in Astronomy and Astrophysics

Published
2018
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7. Characterization of the gaseous companion �� Andromedae b: New Keck and LBTI high-contrast observations

Author

Bonnefoy, M., Currie, T., Marleau, G. -D., Schlieder, J. E., Wisniewski, J., Carson, J., Covey, K. R., Henning, T., Biller, B., Hinz, P., Klahr, H., Boyer, A. N. Marsh, Zimmerman, N., Janson, M., McElwain, M., Mordasini, C., Skemer, A., Bailey, V., Defr��re, D., Thalmann, C., Skrutskie, M., Allard, F., Homeier, D., Tamura, M., Feldt, M., Cumming, A., Grady, C., Brandner, W., Kandori, R., Kuzuhara, M., Fukagawa, M., Kwon, J., Kudo, T., Hashimoto, J., Kusakabe, N., Abe, L., Brandt, T., Egner, S., Guyon, O., Hayano, Y., Hayashi, M., Hayashi, S., Hodapp, K., Ishii, M., Iye, M., Knapp, G., Matsuo, T., Mede, K., Miyama, M., Morino, J. -I., Moro-Martin, A., Nishimura, T., Pyo, T., Serabyn, E., Suenaga, T., Suto, H., Suzuki, R., Takahashi, Takami, M., Takato, N., Terada, H., Tomono, D., Turner, E., Watanabe, M., Yamada, T., Takami, H., and Usuda, T.

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), FOS: Physical sciences, Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

We previously reported the direct detection of a low mass companion at a projected separation of 55+-2 AU around the B9 type star �� Andromedae. The properties of the system (mass ratio, separation) make it a benchmark for the understanding of the formation and evolution of gas giant planets and brown dwarfs on wide-orbits. We present new angular differential imaging (ADI) images of the Kappa Andromedae system at 2.146 (Ks), 3.776 (L'), 4.052 (NB 4.05) and 4.78 ��m (M') obtained with Keck/NIRC2 and LBTI/LMIRCam, as well as more accurate near-infrared photometry of the star with the MIMIR instrument. We derive a more accurate J = 15.86 +- 0.21, H = 14.95 +- 0.13, Ks = 14.32 +- 0.09 mag for �� And b. We redetect the companion in all our high contrast observations. We confirm previous contrasts obtained at Ks and L' band. We derive NB 4.05 = 13.0 +- 0.2 and M' = 13.3 +- 0.3 mag and estimate Log10(L/Lsun) = -3.76 +- 0.06. We build the 1-5 microns spectral energy distribution of the companion and compare it to seven PHOENIX-based atmospheric models in order to derive Teff = 1900+100-200 K. Models do not set constrains on the surface gravity. ``Hot-start" evolutionary models predict masses of 14+25-2 MJup based on the luminosity and temperature estimates, and considering a conservative age range for the system (30+120-10 Myr). ``warm-start" evolutionary tracks constrain the mass to M >= 11 MJup. Therefore, the mass of �� Andromedae b mostly falls in the brown-dwarf regime, due to remaining uncertainties in age and mass-luminosity models. According to the formation models, disk instability in a primordial disk could account for the position and a wide range of plausible masses of �� And b., 20 pages, 16 figures, accepted for publication in Astronomy and Astrophysics on August 6, 2013

Published
2013
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