BANYAN. VI. DISCOVERY OF A COMPANION AT THE BROWN DWARF/PLANET-MASS LIMIT TO A TUCANA-HOROLOGIUM M DWARF

被引：36

作者：

Artigau, Etienne ^{[1
]}

Gagne, Jonathan ^{[1
]}

Faherty, Jacqueline ^{[2
]}

Malo, Lison ^{[3
]}

Naud, Marie-Eve ^{[1
]}

Doyon, Rene ^{[1
]}

Lafreniere, David ^{[1
]}

Beletsky, Yuri ^{[4
]}

机构：

[1] Univ Montreal, Dept Phys, Inst Rech Exoplanetes IREx, Montreal, PQ H3C 3J7, Canada

[2] Carnegie Inst Sci, Dept Terr Magnetism, Washington, DC 20015 USA

[3] Canada France Hawaii Telescope Corp, Kamuela, HI 96743 USA

[4] Carnegie Inst Sci, Las Campanas Observ, La Serena, Chile

来源：

ASTROPHYSICAL JOURNAL | 2015年 / 806卷 / 02期

基金：

美国国家航空航天局; 美国国家科学基金会;

关键词：

brown dwarfs; stars: late-type; stars: low-mass; VERY-LOW MASS; LITHIUM DEPLETION BOUNDARY; GIANT PLANET FORMATION; STAR CANDIDATES; T-DWARFS; KINEMATIC GROUPS; BETA-PICTORIS; NEARBY STARS; YOUNG STARS; LOW-GRAVITY;

D O I：

10.1088/0004-637X/806/2/254

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We report the discovery of a substellar companion to 2MASS J02192210-3925225, a young M6. candidate member of the Tucana-Horologium association (30-40 Myr). This L4 gamma companion has been discovered with seeing-limited direct imaging observations; at a 4 '' separation (160 AU) and a modest contrast ratio, it joins the very short list of young low-mass companions amenable to study without the aid of adaptive optics, enabling its characterization with a much wider suite of instruments than is possible for companions uncovered by highcontrast imaging surveys. With a model-dependent mass of 12-15 M-Jup, it straddles the boundary between the planet and brown dwarf mass regimes. We present near-infrared spectroscopy of this companion and compare it to various similar objects uncovered in the last few years. The J0219-3925 system falls in a sparsely populated part of the host mass versus mass ratio diagram for binaries; the dearth of known similar companions may be due to observational biases in previous low-mass companion searches.

引用

页数：11

共 81 条

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