Discovery of a brown dwarf companion to the star HIP 64892
Creators: name: Cheetham, A.
name: Bonnefoy, M.
name: Desidera, S.
name: Langlois, M.
name: Vigan, A.
name: Schmidt, T.
name: Olofsson, J.
name: Chauvin, G.
name: Klahr, H.
name: Gratton, R.
name: D'Orazi, V.
name: Henning, T.
name: Janson, M.
name: Biller, B.
name: Peretti, S.
name: Hagelberg, J.
name: Ségransan, D.
name: Udry, S.
name: Mesa, D.
name: Sissa, E.
name: Kral, Q.
name: Schlieder, J.
name: Maire, A. -L.
name: Mordasini, C.
name: Menard, F.
name: Zurlo, A.
name: Beuzit, J. -L.
name: Feldt, M.
name: Mouillet, D.
name: Meyer, M.
name: Lagrange, A. -M.
name: Boccaletti, A.
name: Keppler, M.
name: Kopytova, T.
name: Ligi, R.
name: Rouan, D.
name: Coroller, H. Le
name: Dominik, C.
name: Lagadec, E.
name: Turatto, M.
name: Abe, L.
name: Antichi, J.
name: Baruffolo, A.
name: Baudoz, P.
name: Blanchard, P.
name: Buey, T.
name: Carbillet, M.
name: Carle, M.
name: Cascone, E.
name: Claudi, R.
name: Costille, A.
name: Delboulbé, A.
name: De Caprio, V.
name: Dohlen, K.
name: Fantinel, D.
name: Feautrier, P.
name: Fusco, T.
name: Giro, E.
name: Gluck, L.
name: Hubin, N.
name: Hugot, E.
name: Jaquet, M.
name: Kasper, M.
name: Llored, M.
name: Madec, F.
name: Magnard, Y.
name: Martinez, P.
name: Maurel, D.
name: Mignant, D. Le
name: Möller-Nilsson, O.
name: Moulin, T.
name: Origné, A.
name: Pavlov, A.
name: Perret, D.
name: Petit, C.
name: Pragt, J.
name: Puget, P.
name: Rabou, P.
name: Ramos, J.
name: Rigal, F.
name: Rochat, S.
name: Roelfsema, R.
name: Rousset, G.
name: Roux, A.
name: Salasnich, B.
name: Sauvage, J. -F.
name: Sevin, A.
name: Soenke, C.
name: Stadler, E.
name: Suarez, M.
name: Weber, L.
name: Wildi, F.
Publisher: name: arXiv
Year: 2018
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: We report the discovery of a bright, brown dwarf companion to the star HIP 64892, imaged with VLT/SPHERE during the SHINE exoplanet survey. The host is a B9.5V member of the Lower-Centaurus-Crux subgroup of the Scorpius Centaurus OB association. The measured angular separation of the companion ($1.2705\pm0.0023$") corresponds to a projected distance of $159\pm12$ AU. We observed the target with the dual-band imaging and long-slit spectroscopy modes of the IRDIS imager to obtain its SED and astrometry. In addition, we reprocessed archival NACO L-band data, from which we also recover the companion. Its SED is consistent with a young (&lt;30 Myr), low surface gravity object with a spectral type of M9$_γ\pm1$. From comparison with the BT-Settl atmospheric models we estimate an effective temperature of $T_{\textrm{eff}}=2600 \pm 100$ K, and comparison of the companion photometry to the COND evolutionary models yields a mass of $\sim29-37$ M$_{\text{J}}$ at the estimated age of $16^{+15}_{-7}$ Myr for the system. HIP 64892 is a rare example of an extreme-mass ratio system ($q\sim0.01$) and will be useful for testing models relating to the formation and evolution of such low-mass objects.
description: 12 pages, 11 figures, accepted for publication in A&amp;A