Details

Autor(en) / Beteiligte

• Chauvin, G.
• Vigan, A.
• Langlois, M.
• Bonnefoy, M.
• Beuzit, J.-L.
• Feldt, M.
• Mouillet, D.
• Cheetham, A.
• Biller, B.
• Boccaletti, A.
• Galicher, R.
• Hagelberg, J.
• Mesa, D.
• Olofsson, J.
• Samland, M.
• Schmidt, T. O. B.
• Bonavita, M.
• Charnay, B.
• Cudel, M.
• Daemgen, S.
• Delorme, P.
• Janin-Potiron, P.
• Janson, M.
• Keppler, M.
• Le Coroller, H.
• Ligi, R.
• Messina, S.
• Mollière, P.
• Mordasini, C.
• Müller, A.
• Perrot, C.
• Rodet, L.
• Rouan, D.
• Zurlo, A.
• Henning, T.
• Schmid, H.-M.
• Turatto, M.
• Udry, S.
• Antichi, J.
• Baruffolo, A.
• Baudoz, P.
• Baudrand, J.
• Blanchard, P.
• Bazzon, A.
• Buey, T.
• Carbillet, M.
• Charton, J.
• Cascone, E.
• Claudi, R.
• Costille, A.
• Deboulbe, A.
• De Caprio, V.
• Dohlen, K.
• Fantinel, D.
• Feautrier, P.
• Fusco, T.
• Gigan, P.
• Giro, E.
• Gisler, D.
• Gluck, L.
• Hubin, N.
• Hugot, E.
• Jaquet, M.
• Kasper, M.
• Madec, F.
• Magnard, Y.
• Maurel, D.
• Möller-Nilsson, O.
• Llored, M.
• Origné, A.
• Pavlov, A.
• Perret, D.
• Pragt, J.
• Puget, P.
• Rabou, P.
• Ramos, J.
• Rigal, R.
• Roelfsema, R.
• Rousset, G.
• Sauvage, J.-F.
• Sevin, A.
• Soenke, C.
• Stadler, E.
• Suarez, M.
• Weber, L.
• Wildi, F.
• Antoniucci, S.
• Augereau, J.-C.
• Brandner, W.
• Engler, N.
• Girard, J.
• Kral, Q.
• Kopytova, T.
• Lagadec, E.
• Milli, J.
• Moutou, C.
• Schlieder, J.
• Szulágyi, J.
• Thalmann, C.
• Wahhaj, Z.

Titel

Discovery of a warm, dusty giant planet around HIP 65426

Ist Teil von

• Astronomy and astrophysics (Berlin), 2017-09, Vol.605, p.L9

Ort / Verlag

Heidelberg: EDP Sciences

Erscheinungsjahr

2017

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• Aims. The SHINE program is a high-contrast near-infrared survey of 600 young, nearby stars aimed at searching for and characterizing new planetary systems using VLT/SPHERE’s unprecedented high-contrast and high-angular-resolution imaging capabilities. It is also intended to place statistical constraints on the rate, mass and orbital distributions of the giant planet population at large orbits as a function of the stellar host mass and age to test planet-formation theories. Methods. We used the IRDIS dual-band imager and the IFS integral field spectrograph of SPHERE to acquire high-contrast coronagraphic differential near-infrared images and spectra of the young A2 star HIP 65426. It is a member of the ~17 Myr old Lower Centaurus-Crux association. Results. At a separation of 830 mas (92 au projected) from the star, we detect a faint red companion. Multi-epoch observations confirm that it shares common proper motion with HIP 65426. Spectro-photometric measurements extracted with IFS and IRDIS between 0.95 and 2.2 μm indicate a warm, dusty atmosphere characteristic of young low-surface-gravity L5-L7 dwarfs. Hot-start evolutionary models predict a luminosity consistent with a 6–12 MJup, Teff = 1300–1600 K and R = 1.5 ± 0.1 RJup giant planet. Finally, the comparison with Exo-REM and PHOENIX BT-Settl synthetic atmosphere models gives consistent effective temperatures but with slightly higher surface gravity solutions of log (g) = 4.0–5.0 with smaller radii (1.0–1.3 RJup). Conclusions. Given its physical and spectral properties, HIP 65426 b occupies a rather unique placement in terms of age, mass, and spectral-type among the currently known imaged planets. It represents a particularly interesting case to study the presence of clouds as a function of particle size, composition, and location in the atmosphere, to search for signatures of non-equilibrium chemistry, and finally to test the theory of planet formation and evolution.