A candidate substellar companion to CD -33°7795 (TWA 5)

被引:128
作者
Lowrance, PJ [1 ]
McCarthy, C
Becklin, EE
Zuckerman, B
Schneider, G
Webb, RA
Hines, DC
Kirkpatrick, JD
Koerner, DW
Low, F
Meier, R
Rieke, M
Smith, BA
Terrile, RJ
Thompson, RI
机构
[1] Univ Calif Los Angeles, Los Angeles, CA 90024 USA
[2] Univ Arizona, Tucson, AZ USA
[3] CALTECH, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA
[4] Univ Penn, Philadelphia, PA 19104 USA
[5] Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA
[6] CALTECH, Jet Prop Lab, Pasadena, CA USA
基金
美国国家航空航天局;
关键词
stars; low-mass; brown dwarfs;
D O I
10.1086/311858
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present the discovery of a candidate substellar object in a survey of young stars in the solar vicinity using the sensitivity and spatial resolution afforded by the NICMOS coronagraph on the Hubble Space Telescope. The H = 12.1 mag object was discovered approximately 2" from the TW Hydrae association member CD -33 degrees 7795 (TWA 5), and the photometry implies a spectral type M8-M8.5, with a temperature of similar to 2600 K. We estimate that the probability of a chance alignment with a background object of this nature is less than 2 x 10(-5) and therefore postulate that the object (TWA 5B) is physically associated at a projected separation of 100 AU, Given the likely youth of the primary (similar to 10 Myr), current brown dwarf cooling models predict a mass of approximate to 20M(Jup) for TWA 5B.
引用
收藏
页码:L69 / L72
页数:4
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