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1. The cool brown dwarf Gliese 229 B is a close binary

Author

Xuan, Jerry W., Mérand, A., Thompson, W., Zhang, Y., Lacour, S., Blakely, D., Mawet, D., Oppenheimer, R., Kammerer, J., Batygin, K., Sanghi, A., Wang, J., Ruffio, J.-B., Liu, M. C., Knutson, H., Brandner, W., Burgasser, A., Rickman, E., Bowens-Rubin, R., Salama, M., Balmer, W., Blunt, S., Bourdarot, G., Caselli, P., Chauvin, G., Davies, R., Drescher, A., Eckart, A., Eisenhauer, F., Fabricius, M., Feuchtgruber, H., Finger, G., Förster Schreiber, N. M., Garcia, P., Genzel, R., Gillessen, S., Grant, S., Hartl, M., Haußmann, F., Henning, T., Hinkley, S., Hönig, S. F., Horrobin, M., Houllé, M., Janson, M., Kervella, P., Kral, Q., Kreidberg, L., Le Bouquin, J.-B., Lutz, D., Mang, F., Marleau, G.-D., Millour, F., More, N., Nowak, M., Ott, T., Otten, G., Paumard, T., Rabien, S., Rau, C., Ribeiro, D. C., Sadun Bordoni, M., Sauter, J., Shangguan, J., Shimizu, T. T., Sykes, C., Soulain, A., Spezzano, S., Straubmeier, C., Stolker, T., Sturm, E., Subroweit, M., Tacconi, L. J., van Dishoeck, E. F., Vigan, A., Widmann, F., Wieprecht, E., Winterhalder, T. O., and Woillez, J.

Published
2024
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5. MINDS: JWST/NIRCam imaging of the protoplanetary disk PDS 70: A spiral accretion stream and a potential third protoplanet.

Author

Christiaens, V., Samland, M., Henning, Th., Portilla-Revelo, B., Perotti, G., Matthews, E., Absil, O., Decin, L., Kamp, I., Boccaletti, A., Tabone, B., Marleau, G.-D., van Dishoeck, E. F., Güdel, M., Lagage, P.-O., Barrado, D., Caratti o Garatti, A., Glauser, A. M., Olofsson, G., and Ray, T. P.

Subjects
PROTOPLANETARY disks, PLANETESIMALS, NATURAL satellites, RADIATIVE transfer, IMAGE processing, ATMOSPHERIC models, CIRCUMSTELLAR matter, ACCRETION (Astrophysics)
Abstract

Context. Two protoplanets have recently been discovered within the PDS 70 protoplanetary disk. JWST/NIRCam offers a unique opportunity to characterize them and their birth environment at wavelengths that are difficult to access from the ground. Aims. We image the circumstellar environment of PDS 70 at 1.87 μm and 4.83 μm, assess the presence of Pa-α emission due to accretion onto the protoplanets, and probe any IR excess indicative of heated circumplanetary material. Methods. We obtained noncoronagraphic JWST/NIRCam images of PDS 70 within the MIRI mid-INfrared Disk Survey (MINDS) program. We leveraged the Vortex Image Processing (VIP) package for data reduction, and we developed dedicated routines for optimal stellar point spread function subtraction, unbiased imaging of the disk, and protoplanet flux measurement in this type of dataset. A radiative transfer model of the disk was used to separate the contributions from the disk and the protoplanets. Results. We redetect both protoplanets and identify extended emission after subtracting a disk model, including a large-scale spiral-like feature. We interpret its signal in the direct vicinity of planet c as tracing the accretion stream that feeds its circumplanetary disk, while the outer part of the feature may rather reflect asymmetric illumination of the outer disk. We also report a bright signal that is consistent with a previously proposed protoplanet candidate enshrouded in dust near the 1:2:4 mean-motion resonance with planets b and c. The 1.87 μm flux of planet b is consistent with atmospheric model predictions, but the flux of planet c is not. We discuss potential origins for this discrepancy, including significant Pa-α line emission. The 4.83 μm fluxes of planets b and c suggest enshrouding dust or heated CO emission from their circumplanetary environment. Conclusions. The use of image-processing methods that are optimized for extended disk signals on high-sensitivity and high-stability from JWST can uniquely identify signatures of planet–disk interactions and enable accurate photometry of protoplanets at wavelengths that are difficult to probe from the ground. Our results indicate that more protoplanets can be identified and characterized in other JWST datasets. [ABSTRACT FROM AUTHOR]

Published
2024
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8. 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

9. 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

11. 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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12. The B-star Exoplanet Abundance Study (BEAST)

Author

Meyer, M., Janson, M., Gratton, R., Vigan, A., Bonnefoy, M., Mamajek, E., Reffert, S., Marleau, G.-D., Langlois, M., Chauvin, G., Ringqvist, S., Mayer, L., Viswanath, G., Squicciarini, V., Samland, M., Helled, R., Kenworthy, M.A., Quanz, S., Henning, T., Engler, N., Dorazo, V., and Meeus, G.

Abstract

Bulletin of the American Astronomical Society, 54 (6), ISSN:0002-7537, AAS240 Abstracts

Published
2022

13. The SPHERE infrared survey for exoplanets (SHINE)

Author

Vigan, A., Fontanive, C., Meyer, M., Biller, B., Bonavita, M., Feldt, M., Desidera, S., Marleau, G.-D., Emsenhuber, A., Galicher, R., Rice, K., Forgan, D., Mordasini, C., Gratton, R., Le Coroller, H., Maire, A.-L., Cantalloube, F., Chauvin, G., Cheetham, A., Hagelberg, J., Lagrange, A.-M., Langlois, M., Bonnefoy, M., Beuzit, J.-L., Boccaletti, A., D���Orazi, V., Delorme, P., Dominik, C., Henning, Th., Janson, M., Lagadec, E., Lazzoni, C., Ligi, R., Menard, F., Mesa, D., Messina, S., Moutou, C., M��ller, A., Perrot, C., Samland, M., Schmid, H. M., Schmidt, T., Sissa, E., Turatto, M., Udry, S., Zurlo, A., Abe, L., Antichi, J., Asensio-Torres, R., Baruffolo, A., Baudoz, P., Baudrand, J., Bazzon, A., Blanchard, P., Bohn, A. J., Brown Sevilla, S., Carbillet, M., Carle, M., Cascone, E., Charton, J., Claudi, R., Costille, A., De Caprio, V., Delboulb��, A., Dohlen, K., Engler, N., Fantinel, D., Feautrier, P., Fusco, T., Gigan, P., Girard, J. H., Giro, E., Gisler, D., Gluck, L., Gry, C., Hubin, N., Hugot, E., Jaquet, M., Kasper, M., Le Mignant, D., Llored, M., Madec, F., Magnard, Y., Martinez, P., Maurel, D., M��ller-Nilsson, O., Mouillet, D., Moulin, T., Orign��, A., Pavlov, A., Perret, D., Petit, C., Pragt, J., Puget, P., Rabou, P., Ramos, J., Rickman, E. L., Rigal, F., Rochat, S., Roelfsema, R., Rousset, G., Roux, A., Salasnich, B., Sauvage, J.-F., Sevin, A., Soenke, C., Stadler, E., Suarez, M., Wahhaj, Z., Weber, L., Wildi, F., 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, 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
[PHYS.ASTR.IM]Physics [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], 530 Physics, 520 Astronomy, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Earth and Planetary Astrophysics, 620 Engineering, Astrophysics::Galaxy Astrophysics
Abstract

International audience; The SpHere INfrared Exoplanet (SHINE) project is a 500-star survey performed with SPHERE on the Very Large Telescope for the purpose of directly detecting new substellar companions and understanding their formation and early evolution. Here we present an initial statistical analysis for a subsample of 150 stars spanning spectral types from B to M that are representative of the full SHINE sample. Our goal is to constrain the frequency of substellar companions with masses between 1 and 75 M Jup and semimajor axes between 5 and 300 au. For this purpose, we adopt detection limits as a function of angular separation from the survey data for all stars converted into mass and projected orbital separation using the BEX-COND-hot evolutionary tracks and known distance to each system. Based on the results obtained for each star and on the 13 detections in the sample, we use a Markov chain Monte Carlo tool to compare our observations to two different types of models. The first is a parametric model based on observational constraints, and the second type are numerical models that combine advanced core accretion and gravitational instability planet population synthesis. Using the parametric model, we show that the frequencies of systems with at least one substellar companion are 23.0 −9.7 +13.5 , 5.8 −2.8 +4.7 , and 12.6 −7.1 +12.9 % for BA, FGK, and M stars, respectively. We also demonstrate that a planet-like formation pathway probably dominates the mass range from 1–75 M Jup for companions around BA stars, while for M dwarfs, brown dwarf binaries dominate detections. In contrast, a combination of binary star-like and planet-like formation is required to best fit the observations for FGK stars. Using our population model and restricting our sample to FGK stars, we derive a frequency of 5.7 −2.8 +3.8 %, consistent with predictions from the parametric model. More generally, the frequency values that we derive are in excellent agreement with values obtained in previous studies.

Published
2021
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17. 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

18. 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

20. Characterization of the Gaseous Companion k 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, Defrere, D, Thalmann, C, Skrutskie, M, Allard, F, Homeier, D, Tamura, M, and Grady, C

Subjects
Astronomy
Abstract

Context. We previously reported the direct detection of a low mass companion at a projected separation of 55+/-2 astronomical units around the B9 type star kappa 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. Aims. We present new angular differential imaging (ADI) images of the system at 2.146 (K(sub s)), 3.776 (L'), 4.052 (NB 4.05) and 4.78 micrometers (M') obtained with Keck/NIRC2 and LBTI/LMIRCam, as well as more accurate near-infrared photometry of the star with the MIMIR instrument. We aim to determine the near-infrared spectral energy distribution (SED) of the companion and use it to characterize the object. Methods. We used analysis methods adapted to ADI to extract the companion flux. We compared the photometry of the object to reference young/old objects and to a set of seven PHOENIX-based atmospheric models of cool objects accounting for the formation of dust. We used evolutionary models to derive mass estimates considering a wide range of plausible initial conditions. Finally, we used dedicated formation models to discuss the possible origin of the companion. Results. We derive a more accurate J = 15.86 +/- 0.21, H = 14.95 +/- 0.13, K(sub s) = 14.32 +/- 0.09 mag for kappa And b. We redetect the companion in all our high contrast observations. We confirm previous contrasts obtained at K(sub s) and L' band. We derive NB 4.05 = 13.0 +/- 0.2 and M' = 13.3 +/- 0.3 mag and estimate Log(base 10)(L/solar luminosity) = −3.76 +/- 0.06. Atmospheric models yield T(sub eff) = 1900(+100/−200) K. They do not set constrains on the surface gravity. "Hot-start" evolutionary models predict masses of 14(+25/−2) Jupiter mass based on the luminosity and temperature estimates, and considering a conservative age range for the system (30(+120/−10) million years). "warm-start" evolutionary tracks constrain the mass to M greater than or equal to 11 Jupiter mass. Conclusions. The mass of kappa 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 kappa and b.

Published
2013

21. The GJ 504 system revisited

Author

Bonnefoy, M., Perraut, K., Lagrange, A.-M., Delorme, P., Vigan, A., Line, M., Rodet, L., Ginski, C., Mourard, D., Marleau, G.-D., Samland, M., Tremblin, P., Ligi, R., Cantalloube, F., Mollière, P., Charnay, B., Kuzuhara, M., Janson, M., Morley, C., Homeier, D., D’orazi, V., Klahr, H., Mordasini, C., Lavie, B., Baudino, J.-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, J.-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, Daniel, 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, F., Weber, L., 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), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Laboratoire 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), 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 National de Recherche en Informatique et en Automatique (Inria), 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'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), 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, Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Eberhard Karls Universität Tübingen = Eberhard Karls University of Tuebingen, DOTA, ONERA, Université Paris Saclay (COmUE) [Palaiseau], ONERA-Université Paris Saclay (COmUE), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), 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), Stockholm University, École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Observatoire de Paris, and Université Paris sciences et lettres (PSL)

Subjects
[SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

International audience; Context. The G-type star GJ504A is known to host a 3–35 M Jup companion whose temperature, mass, and projected separation all contribute to making it a test case for planet formation theories and atmospheric models of giant planets and light brown dwarfs. Aims. We aim at revisiting the system age, architecture, and companion physical and chemical properties using new complementary interferometric, radial-velocity, and high-contrast imaging data. Methods. We used the CHARA interferometer to measure GJ504A’s angular diameter and obtained an estimation of its radius in combinationwith the H IPPARCOS parallax. The radius was compared to evolutionary tracks to infer a new independent age range for the system. We collected dual imaging data with IRDIS on VLT/SPHERE to sample the near-infrared (1.02–2.25 μ m) spectral energy distribution (SED) of the companion. The SED was compared to five independent grids of atmospheric models ( petitCODE , Exo-REM , BT-SETTL , Morley et al., and ATMO ) to infer the atmospheric parameters of GJ 504b and evaluate model-to-model systematic errors. In addition, we used a specific model grid exploring the effect of different C/O ratios. Contrast limits from 2011 to 2017 were combined with radial velocity data of the host star through the MESS2 tool to define upper limits on the mass of additional companions in the system from 0.01 to 100 au. We used an MCMC fitting tool to constrain the companion’sorbital parameters based on the measured astrometry, and dedicated formation models to investigate its origin. Results. We report a radius of 1.35 ± 0.04 R ⊙ for GJ504A. The radius yields isochronal ages of 21 ± 2 Myr or 4.0 ± 1.8 Gyr for the system and line-of-sight stellar rotation axis inclination of 162.4 −4.3 +3.8 degrees or 186.6 −3.8 +4.3 degrees. We re-detect the companion in the Y2, Y3, J3, H2, and K1 dual-band images. The complete 1–4 μ m SED shape of GJ504b is best reproduced by T8-T9.5 objects with intermediate ages (≤ 1.5Gyr), and/or unusual dusty atmospheres and/or super-solar metallicities. All atmospheric models yield T eff = 550 ± 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 log L ∕ L ⊙ = −6.15 ± 0.15 dex for the companion from the empirical analysis and spectral synthesis. The luminosity and T eff yield masses of M = 1.3 −0.3 +0.6 M Jup and M = 23 −9 +10 M Jup for the young and old age ranges, respectively. The semi-major axis (sma) is above 27.8 au and the eccentricity is lower than 0.55. The posterior on GJ 504b’s orbital inclination suggests a misalignment with the rotation axis of GJ 504A. We exclude additional objects (90% prob.) more massive than 2.5 and 30 M Jup with semi-major axes in the range 0.01–80 au for the young and old isochronal ages, respectively. Conclusions. The mass and semi-major axis of GJ 504b are marginally compatible with a formation by disk-instability if the system is 4 Gyr old. The companion is in the envelope of the population of planets synthesized with our core-accretion model. Additional deep imaging and spectroscopic data with SPHERE and JWST should help to confirm the possible spin-orbit misalignment and refine the estimates on the companion temperature, luminosity, and atmospheric composition.

Published
2018
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22. 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 - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), 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), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), 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 Paris-Sud - Paris 11 (UP11)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), École normale supérieure - Paris (ENS Paris)-École normale supérieure - Paris (ENS Paris), PSL Research University (PSL), ONERA, Laboratoire de Chimie, Ingénierie Moléculaire et Matériaux d'Angers (CIMMA), 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)-Centre National de la Recherche Scientifique (CNRS), 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 National de la Recherche Scientifique (CNRS)-Université d'Angers (UA), 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, School of Earth and Space Exploration, Arizona State University, P.O. Box 871404, Tempe, Leiden Observatory, Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA), Physikalisches Institut, Universitat Bern, Gesellschaftsstrasse 6, 3012, Bern, Switzerland, Commissariat à l'énergie atomique et aux énergies alternatives (CEA), INAF-Osservatorio Astronomico di Brera (INAF-OAB), Haute résolution angulaire en astrophysique, 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), Pôle Planétologie du LESIA, Astrobiology Center of NINS (ABC), National Institutes of Natural Sciences [Tokyo] (NINS), Department of Astronomy, Stockholm University, AlbaNova University Center, 106 91, Stockholm, Sweden, Harvard University, ISDC, Geneva Observatory, University of Geneva, Instituto de Astronomia y Ciencias Planetarias de Atacama, Copayapu 485, Copiap, Atacama, Chile, Laboratoire Franco-Chilien d'Astronomie, UMI 3386, Institute for Advanced Study, Einstein Drive, Princeton, Exoplanets and Stellar Astrophysics Laboratory, NASA Goddard Space Flight Center, European Southern Observatory (ESO), Institute for Astronomy, Department of Physics, ETH Zürich, Nucleo de Astronomia, Facultad de Ingenieria y Ciencias, Universidad Diego Portales, Av. 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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23. Discovery of a planetary-mass companion within the gap of the transition disk around PDS 70

Author

Keppler, M., Benisty, M., Müller, A., Henning, Th., van Boekel, R., Cantalloube, F., Ginski, C., van Holstein, R. G., Maire, A. -L., Pohl, A., Samland, M., Avenhaus, H., Baudino, J. -L., Boccaletti, A., de Boer, J., Bonnefoy, M., Chauvin, G., Desidera, S., Langlois, M., Lazzoni, C., Marleau, G. -D., Mordasini, C., Pawellek, N., Stolker, T., Vigan, A., Zurlo, A., Birnstiel, T., Brandner, W., Feldt, M., Flock, M., Girard, J., Gratton, R., Hagelberg, J., Isella, A., Janson, M., Juhasz, A., Kemmer, J., Kral, Q., Lagrange, A. -M., Launhardt, R., Matter, A., Ménard, F., Milli, J., Mollière, P., Olofsson, J., Pérez, L., Pinilla, P., Pinte, C., Quanz, S. P., Schmidt, T., Udry, S., Wahhaj, Z., Williams, J. P., Buenzli, E., Cudel, M., Dominik, C., Galicher, R., Kasper, M., Lannier, J., Mesa, D., Mouillet, D., Peretti, S., Perrot, C., Salter, G., Sissa, E., Wildi, F., Abe, L., Antichi, J., Augereau, J. -C., Baruffolo, A., Baudoz, P., Bazzon, A., Beuzit, J. -L., Blanchard, P., Brems, S. S., Buey, T., De Caprio, V., Carbillet, M., Carle, M., Cascone, E., Cheetham, A., Claudi, R., Costille, A., Delboulbé, A., Dohlen, K., Fantinel, D., Feautrier, P., Fusco, T., Giro, E., Gluck, L., Gry, C., Hubin, N., Hugot, E., Jaquet, M., Le Mignant, D., Llored, M., Madec, F., Magnard, Y., Martinez, P., Maurel, D., Meyer, M., Möller-Nilsson, O., Moulin, T., Mugnier, L., Origné, A., Pavlov, A., Perret, D., Petit, C., Pragt, J., Puget, P., Rabou, P., Ramos, J., Rigal, F., Rochat, S., Roelfsema, R., Rousset, G., Roux, A., Salasnich, B., Sauvage, J. -F., Sevin, A., Soenke, C., Stadler, E., Suarez, M., and Weber, M. Turatto and L.

Published
2018

24. A faint companion around CrA-9: protoplanet or obscured binary?

Author

Christiaens, V, Ubeira-Gabellini, M-G, Cánovas, H, Delorme, P, Pairet, B, Absil, O, Casassus, S, Girard, J H, Zurlo, A, Aoyama, Y, Marleau, G-D, Spina, L, van der Marel, N, Cieza, L, Lodato, G, Pérez, S, Pinte, C, Price, D J, and Reggiani, M

Subjects
GAS giants, SYNCOPE, HIGH temperatures, ORIGIN of planets, ASTROMETRY
Abstract

Understanding how giant planets form requires observational input from directly imaged protoplanets. We used VLT/NACO and VLT/SPHERE to search for companions in the transition disc of 2MASS J19005804-3645048 (hereafter CrA-9), an accreting M0.75 dwarf with an estimated age of 1–2 Myr. We found a faint point source at ∼0.7-arcsec separation from CrA-9 (∼108 au projected separation). Our 3-epoch astrometry rejects a fixed background star with a 5σ significance. The near-IR absolute magnitudes of the object point towards a planetary-mass companion. However, our analysis of the 1.0–3.8 |$\,\mu$| m spectrum extracted for the companion suggests it is a young M5.5 dwarf, based on both the 1.13- μ m Na index and comparison with templates of the Montreal Spectral Library. The observed spectrum is best reproduced with high effective temperature (⁠|$3057^{+119}_{-36}$| K) BT-DUSTY and BT-SETTL models, but the corresponding photometric radius required to match the measured flux is only |$0.60^{+0.01}_{-0.04}$| Jovian radius. We discuss possible explanations to reconcile our measurements, including an M-dwarf companion obscured by an edge-on circum-secondary disc or the shock-heated part of the photosphere of an accreting protoplanet. Follow-up observations covering a larger wavelength range and/or at finer spectral resolution are required to discriminate these two scenarios. [ABSTRACT FROM AUTHOR]

Published
2021
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25. Multi-physics DONJON5 reactor models for improved fuel cycle simulation with CLASS

Author

Billiet Gabriel, Doligez Xavier, Marleau Guy, Ernoult Marc, Hébert Alain, and Thiollière Nicolas

Subjects
Nuclear engineering. Atomic power, TK9001-9401
Abstract

This work investigates reactor model biases and their consequences in nuclear scenario simulations. Usually, the models for Pressurized Water Reactors are based on infinite 2D assembly depletion simulations, but recent work has shown the importance of 3D complete core simulation for uncertainty reduction. The consideration of a whole core leads to new reactor parameters in the simulations that may bring additional biases. The fuel temperature distribution is one of them, and previous work considered isothermal reactors, leading to probable uncertainties in spent fuel inventory at reactor discharge. To quantify those biases and their propagation in a full scenario simulation, new advanced reactor models have been developed, based on neutronics and thermal-hydraulics couplings at the core level performed with DONJON5. Results show that the plutonium isotopic quality of spent fuel is biased for an isothermal core, with values systematically higher than for multi-physics calculations. In order to propagate those discrepancies in fuel cycle simulations that involve plutonium recycling in PWR MOX fuels, the coupling between CLASS and DONJON was renewed in order to add new fuel parameters such as the fuel temperature in the core burn-up simulation. A new methodology for data interpolation from lattice calculation has been implemented that allows acceptable computational time for DONJON5 calculations that are done within the fuel cycle simulation performed by CLASS. Comparison between isothermal and multi-physics reactor models for advanced scenario simulations performed with CLASS shows that the isothermal hypothesis leads to biases up to 10% for plutonium inventory in the UOX spent fuel stockpile, comparable with biases associated with other reactor parameters such as the loading pattern.

Published
2024
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27. Characterization of exoplanets from their formation III. The statistics of planetary luminosities.

Author

Mordasini, C., Marleau, G.-D., and Mollière, P.

Subjects
*EXTRASOLAR planets, *STAR formation, *LUMINOSITY, *ASTRONOMICAL observations, *NATURAL satellites
Abstract

Context. A first characterization of extrasolar planets by the observational determination of the radius has recently been achieved for a large number of planets. For some planets, a measurement of the luminosity has also been possible, with many more directly imaged planets expected in the near future. The statistical characterization of exoplanets through their mass-radius and mass-luminosity diagram is becoming possible. This is for planet formation and evolution theory of similar importance as the mass-distance diagram. Aims. Our aim is to extend our planet-formation model into a coupled formation and evolution model. We want to calculate from one single model in a self-consistent way all basic quantities describing a planet: its mass, semimajor axis, composition, radius, and luminosity. We then want to use this model for population synthesis calculations. Methods. In this and a companion paper, we show how we solve the structure equations describing the gaseous envelope of a protoplanet during the early-formation phase, the gas runaway accretion phase, and the evolutionary phase at constant mass on Gyr timescales. We improve the model further with a new prescription for the disk-limited gas accretion rate, an internal structure model for the planetary core assuming a differentiated interior, and the inclusion of radioactive decay as an additional heat source in the core. Results. We study the in situ formation and evolution of Jupiter, the mass-radius relationship of giant planets, the influence of the core mass on the radius, and the luminosity both in the "hot start" and the "cold start" scenario. Special emphasis is placed on the validation of the model by comparing it with other models of planet formation and evolution. We find that our results agree very well with those of more complex models, despite a number of simplifications we make in our calculations. Conclusions. The upgraded model yields the most important physical quantities describing a planet from its beginning as a tiny seed embryo to a Gyr-old planet. This is the case for all planets in a synthetic planetary population. Therefore, we can now use self-consistently the observational constraints coming from all major observational techniques. This is important in a time where different techniques yield constraints on very diverse sub-populations of planets, and where it is difficult to put all these constraints together in one coherent picture. Our comprehensive formation and evolution model should be helpful in this situation for the understanding of exoplanets. [ABSTRACT FROM AUTHOR]

Published
2018
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29. Nuclear Data uncertainty analysis using the coupling of DRAGON with SUSD3D

Author

Adrien Bidaud, Marleau, G., Noblat, E., Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS), and Vernay, Emmanuelle

Subjects
[PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
Abstract

CD Rom ISBN 9780894480690; International audience

Published
2009

31. Study of CANDU thorium-based fuel cycles by deterministic and Monte Carlo methods

Author

Nuttin, A., Guillemin, P., Courau, T., Marleau, G., Méplan, O., David, S., Michel-Sendis, F., Wilson, J.N., Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and bibliotheque, LPSC

Subjects
CANDU reactor, Monte Carlo code MCNP, [PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], DRAGON code, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], thorium
Abstract

In the framework of the Generation IV forum, there is a renewal of interest in self-sustainable thorium fuel cycles applied to various concepts such as Molten Salt Reactors [1,2] or High Temperature Reactors [3,4]. Precise evaluations of the U-233 production potential relying on existing reactors such as PWRs [5] or CANDUs [6] are hence necessary. As a consequence of its design (online refueling and D2O moderator in a thermal spectrum), the CANDU reactor has moreover an excellent neutron economy and consequently a high fissile conversion ratio [7]. For these reasons, we try here, with a shorter term view, to re-evaluate the economic competitiveness of once-through thorium-based fuel cycles in CANDU [8]. Two simulation tools are used: the deterministic Canadian cell code DRAGON [9] and MURE [10], a C++ tool for reactor evolution calculations based on the Monte Carlo code MCNP [11].

Published
2006

33. Characterization of the gaseous companion κ 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., Marsh Boyer, A. N., Zimmerman, N., Janson, M., McElwain, M., Mordasini, C., Skemer, A., Bailey, V., Defrère, D., and Thalmann, C.

Subjects
ASTRONOMICAL observations, BROWN dwarf stars, STAR formation, ASTRONOMICAL photometry, ADAPTIVE optics, DISKS (Astrophysics), ANDROMEDA Galaxy, PLANETARY orbits
Abstract

Context. We previously reported the direct detection of a low-mass companion at a projected separation of 55 ± 2 AU around the B9-type star κ Andromedae. The properties of the system (mass ratio, separation) make it a benchmark for understanding the formation and evolution of gas giant planets and brown dwarfs on wide orbits. Aims. We present new angular differential imaging (ADI) images of the system at 2.146 (Ks), 3.776 (L'), 4.052 (NB_4:05), and 4.78 μm (M') obtained with Keck/NIRC2 and LBTI/LMIRCam, as well as more accurate near-infrared photometry of the star with the MIMIR instrument. We aim to determine the near-infrared spectral energy distribution of the companion and use it to characterize the object. Methods. We used analysis methods adapted to ADI to extract the companion flux. We compared the photometry of the object to reference young, and old objects and to a set of seven PHOENIX-based atmospheric models of cool objects accounting for the formation of dust. We used evolutionary models to derive mass estimates considering a wide range of plausible initial conditions. Finally, we used dedicated formation models to discuss the possible origin of the companion. Results. We derive a more accurate J = 15:86 ± 0:21, H = 14:95 ± 0:13, Ks = 14:32 ± 0:09 mag for κ And b. We detect 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/L☉) =-3:76 ± 0:06. Atmospheric models yield Teff = 1900+100 -200 K. They do not set any constraint on the surface gravity. "Hotstart" evolutionary models predict masses of 14+25 -2 MJup based on the luminosity and temperature estimates, and when considering a conservative age range for the system (30+120 -10 Myr), "warm-start" evolutionary tracks constrain the mass to M ⩾ 10 MJup. Conclusions. The mass of κ Andromedae b mostly falls in the brown-dwarf regime, owing to remaining uncertainties in age and in mass-luminosity models. According to the formation models, disk instability in a primordial disk may account for the position and a wide range of plausible masses of κ And b. [ABSTRACT FROM AUTHOR]

Published
2014
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34. DONJON5/CLASS coupled simulations of MOX/UO2 heterogeneous PWR core

Author

Paradis Maxime, Doligez Xavier, Marleau Guy, Ernoult Marc, and Thiollière Nicolas

Subjects
Nuclear engineering. Atomic power, TK9001-9401
Abstract

Most fuel cycle simulation tools are based either on fixed recipes or assembly calculations for reactor modeling. Due to the high number of calculations and extensive computational power requirements, full-core computations are often seen as not viable for this purpose. However, this leads to additional hypotheses and modeling biases, thus limiting the realism of the resulting fuel cycle. For several applications, the current modeling method is sufficient, but precise calculations of discharged fuel composition may require further refinements. CLASS (Core Library for Advanced Simulation Scenarios) is a dynamic fuel cycle simulation code developed since 2012 with reactor models based on neural networks to produce nuclear data and physical quantities. Past work has shown a first coupling between CLASS and DONJON5 to quantify neural networks approach biases. This work assesses the applicability of 3D full-core diffusion calculations using the DONJON5 code coupled with nuclear scenario simulations involving a realistic PWR core at equilibrium cycle conditions. DONJON5 interpolates burnup dependent diffusion coefficients and cross sections generated beforehand by DRAGON5, a deterministic lattice calculation tool. Whereas previous studies considered only homogeneous reactors (i.e. homogeneous assembly in terms of composition and enrichment as well as homogeneous core), the present contribution focuses on the integration of full-core calculations in CLASS for fuel cycles involving a MOX/UO2 PWR core (i.e. 1/3 MOx–2/3 UOx). The DONJON5 model considered in this work describes a core with critical boron concentration at each time step partially loaded with MOx heterogeneous assemblies composed of three enrichments. In fuel cycle calculations, the main issue is to adapt, in the fabrication stage, the fresh fuel composition for the reactor with regards to the isotopic composition of the available stocks. This work presents a fuel loading model based on power peaking factors minimization that respects irradiation cycle length, 235U enrichment as well as Pu concentration and fissile quality, hence, ensuring a more uniform power distribution in the core.

Published
2022
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35. The Millennium Run Observatory: first light.

Author

Overzier, R., Lemson, G., Angulo, R. E., Bertin, E., Blaizot, J., Henriques, B. M. B., Marleau, G.-D., and White, S. D. M.

Subjects
GALAXIES, TELESCOPES, SCIENTIFIC observation, SIMULATION methods & models, COMPARATIVE studies
Abstract

Simulations of galaxy evolution aim to capture our current understanding as well as to make predictions for testing by future experiments. Simulations and observations are often compared in an indirect fashion: physical quantities are estimated from the observational data and compared to models. However, many applications can benefit from a more direct approach, where the observing process is also simulated, so that the models are seen fully from the observer's perspective. To facilitate this, we have developed the Millennium Run Observatory (MRObs), a theoretical virtual observatory which uses virtual telescopes to 'observe' semianalytic galaxy formation simulations based on the suite of Millennium Run (MR) dark matter simulations. The MRObs produces data that can be processed and analysed using the standard observational software packages developed for real observations. At present, we produce images in 40 filters covering the rest-frame ultraviolet to infrared for two stellar population synthesis models, for three different models of absorption by the intergalactic medium, and in two cosmologies (Wilkinson Microwave Anisotropy Probe year 1 and 7). Galaxy distributions for a large number of mock light cones can be 'observed' using models of major ground- and space-based telescopes. The data include light cone catalogues linked to structural properties of galaxies, pre-observation model images, mock telescope images and Source Extractor products that can all be traced back to the higher level dark matter, semi-analytic galaxy and light cone catalogues available in the MR data base. Here, we describe our methods and announce a first public release of simulated observations that emulate a large number of extragalactic surveys [e.g. Sloan Digital Sky Survey, Canada-France-Hawaii Telescope Legacy Survey (CFHT-LS), Great Observatories Origins Deep Survey (GOODS), GOODS/Early Release Science (ERS), Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey (CANDELS) and Hubble Ultra Deep Field (HUDF)]. The MRObs browser, an online tool, further facilitates exploration of the simulated data. We demonstrate the benefits of a direct approach through a number of example applications: (1) deep galaxy number counts in the CANDELS survey; (2) observed properties of galaxy clusters; (3) structural parameters of galaxies; and (4) identification of dropout galaxies. The MRObs enhances the range of questions that can be asked of semianalytic models, allowing observers and theorists to work towards each other with virtually complete freedom of where to meet. [ABSTRACT FROM AUTHOR]

Published
2013
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36. Simulation Strategy for the Evaluation of Neutronic Properties of a Canadian SCWR Fuel Channel.

Author

Harrisson, G. and Marleau, G.

Subjects
*NUCLEAR energy, *NUCLEAR reactions, *ENERGY research, *FUEL, *POWER resources
Abstract

The Canadian Supercritical-Water-Cooled Reactor (SCWR) is a vertical pressure tube reactor cooled with supercritical light water and moderated with heavy water. For normal operation, the local conditions of the coolant (density and temperature) and fuel (temperature) vary substantially along the channel. This means that to simulate adequately the behavior of the core under operating conditions or for anticipated accident scenario, expensive 3D transport calculations for a complete fuel channel are required. Here, we propose a simulation strategy that takes into account axial variations of the local conditions and avoids 3D transport calculations. This strategy consists in replacing the 3D simulation by a series of isolated 2D calculations followed by a single 1D simulation. It is shown that this strategy is efficient because the axial coupling along the fuel channel is relatively weak. In addition, the neutronic properties of a channel with axial reflector can be modeled using a simplified 3D transport calculation. [ABSTRACT FROM AUTHOR]

Published
2013
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37. A model for coolant void reactivity evaluation in assemblies of CANDU cells

Author

Talebi, F., Marleau, G., and Koclas, J.

Subjects
*NUCLEAR reactors, *CHEMICAL kinetics, *PARTICLES (Nuclear physics), *FUEL
Abstract

Abstract: Coolant void reactivity is a very important safety parameter in CANDU reactor analysis. Here we evaluate the coolant void reactivity in a 2×2 heterogeneous assembly of CANDU cells using the code DRAGON. Since the current version of DRAGON can only treat the coolant void reactivity for a single CANDU cell, an approximate model for the geometry must be considered to perform assembly calculations in a 2×2 pattern. The model we propose consists of replacing the annular fuel pins by equivalent square fuel pins. The equivalence between annular fuel pins and square fuel pins is brought about by homogenizing the fuel plus its sheath and subsequently conserving the reaction rates between the two geometries using a SPH equivalence procedure. The approximate CANDU cells constructed using square pins were used to perform the transport calculations in 2×2 assembly patterns. In addition, the model was used to evaluate coolant void reactivity in 2×2 checkerboard voiding patterns. These calculations reflect more accurately the actual voiding situation being studied. This helps in assessing the effects due to the coupling of neutrons born in one cell to those born in the neighbouring cells. [Copyright &y& Elsevier]

Published
2006
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