DISCOVERY OF THE COLDEST IMAGED COMPANION OF A SUN-LIKE STAR
DISCOVERY OF THE COLDEST IMAGED COMPANION OF A SUN-LIKE STAR
复制标题
类太阳恒星最冷的伴星图像的发现
DOI：
10.1088/0004-637x/707/2/l123
复制
发表时间：
2009
期刊：
影响因子：
--
通讯作者：
U. Hawaii
中科院分区：
文献类型：
--
作者：
C. Thalmann;J. Carson;M. Janson;M. Goto;M. McElwain;S. Egner;M. Feldt;J. Hashimoto;Y. Hayano;T. Henning;K. Hodapp;R. Kandori;H. Klahr;T. Kudo;N. Kusakabe;C. Mordasini;J. Morino;H. Suto;R. Suzuki;Motohide Tamura Max Planck Institute for Astronomy;College of Charleston;U. Toronto;P. University;Subaru Telescope;N. A. O. Japan;Institute for Astronomy;U. Hawaii
我们发现了一颗褐矮星或可能的行星，它在星星GJ 758周围的投影距离为1.“9 = 29 Au，将其置于亚恒星同伴通过核心吸积（105 Au）或直接引力坍缩（通常为100 Au）形成的距离之间。该物体是通过Subaru/HiCIAO对其热辉光直接成像而探测到的。GJ 758 B的质量是木星的10-40倍，温度为550-640 K，是为数不多的已知T型伴星之一，也是迄今为止在类太阳星星周围的热光成像中最冷的伴星。它的轨道可能是偏心的，大小与冥王星的轨道相当，可能是引力散射或向外迁移的结果。一个候选的第二个伴星在一个历元的1.“2处被探测到。
We present the discovery of a brown dwarf or possible planet at a projected separation of 1.″9 = 29 AU around the star GJ 758, placing it between the separations at which substellar companions are expected to form by core accretion (∼5 AU) or direct gravitational collapse (typically ≳100 AU). The object was detected by direct imaging of its thermal glow with Subaru/HiCIAO. At 10–40 times the mass of Jupiter and a temperature of 550–640 K, GJ 758 B constitutes one of the few known T-type companions, and the coldest ever to be imaged in thermal light around a Sun-like star. Its orbit is likely eccentric and of a size comparable to Pluto's orbit, possibly as a result of gravitational scattering or outward migration. A candidate second companion is detected at 1.″2 at one epoch.