First VLTI/GRAVITY Observations of HIP 65426 b: Evidence for a Low or Moderate Orbital Eccentricity
- Creators
- Blunt, Sarah
- Balmer, W. O.
- Wang, J. J.
- Lacour, S.
- Petrus, S.
- Bourdarot, G.
- Kammerer, J.
- Pourré, N.
- Rickman, E.
- Shangguan, J.
- Winterhalder, T.
- Abuter, R.
- Amorim, A.
- Asensio-Torres, R.
- Benisty, M.
- Berger, J. -P.
- Beust, H.
- Boccaletti, A.
- Bohn, A.
- Bonnefoy, M.
- Bonnet, H.
- Brandner, W.
- Cantalloube, F.
- Caselli, P.
- Charnay, B.
- Chauvin, G.
- Chavez, A.
- Choquet, E.
- Christiaens, V.
- Clénet, Y.
- Du Foresto, V. Coudé
- Cridland, A.
- Dembet, R.
- Drescher, A.
- Duvert, G.
- Eckart, A.
- Eisenhauer, F.
- Feuchtgruber, H.
- Garcia, P.
- Garcia Lopez, R.
- Gendron, E.
- Genzel, R.
- Gillessen, S.
- Girard, J. H.
- Haubois, X.
- Heißel, G.
- Henning, Th.
- Hinkley, S.
- Hippler, S.
- Horrobin, M.
- Houllé, M.
- Hubert, Z.
- Jocou, L.
- Keppler, M.
- Kervella, P.
- Kreidberg, L.
- Lagrange, A. -M.
- Lapeyrère, V.
- Le Bouquin, J. -B.
- Léna, P.
- Lutz, D.
- Maire, A. -L.
- Mang, F.
- Marleau, G. -D.
- Mérand, A.
- Mollière, P.
- Monnier, J. D.
- Mordasini, C.
- Mouillet, D.
- Nasedkin, E.
- Nowak, M.
- Ott, T.
- Otten, G. P. P. L.
- Paladini, C.
- Paumard, T.
- Perraut, K.
- Perrin, G.
- Pfuhl, O.
- Pueyo, L.
- Rameau, J.
- Rodet, L.
- Rustamkulov, Z.
- Shimizu, T.
- Sing, D.
- Stolker, T.
- 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.
- Others:
- Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA) ; Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris ; Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
- Institut de Planétologie et d'Astrophysique de Grenoble (IPAG) ; Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ) ; Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France
- Laboratoire d'Astrophysique de Marseille (LAM) ; Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)
- Observatoire de la Côte d'Azur (OCA) ; Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Description
Giant exoplanets have been directly imaged over orders of magnitude of orbital separations, prompting theoretical and observational investigations of their formation pathways. In this paper, we present new VLTI/GRAVITY astrometric data of HIP 65426 b, a cold, giant exoplanet which is a particular challenge for most formation theories at a projected separation of 92 au from its primary. Leveraging GRAVITY's astrometric precision, we present an updated eccentricity posterior that disfavors large eccentricities. The eccentricity posterior is still prior dependent, and we extensively interpret and discuss the limits of the posterior constraints presented here. We also perform updated spectral comparisons with self-consistent forward-modeled spectra, finding a best-fit ExoREM model with solar metallicity and C/O = 0.6. An important caveat is that it is difficult to estimate robust errors on these values, which are subject to interpolation errors as well as potentially missing model physics. Taken together, the orbital and atmospheric constraints paint a preliminary picture of formation inconsistent with scattering after disk dispersal. Further work is needed to validate this interpretation. Analysis code used to perform this work is available on GitHub: https://github.com/sblunt/hip65426.
Abstract
International audience
Additional details
- URL
- https://insu.hal.science/insu-04479028
- URN
- urn:oai:HAL:insu-04479028v1
- Origin repository
- UNICA