Southern very low mass stars and brown dwarfs in wide binary and multiple systems

被引:47
作者
Caballero, Jose Antonio [1 ]
机构
[1] Max Planck Inst Astron, D-69117 Heidelberg, Germany
关键词
binaries : visual; stars : formation; stars : individual (2MASS J23310161-0406193 AB; HD; 221356; LP; 655-23); stars; low-mass; brown dwarfs;
D O I
10.1086/520873
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
The results of the Konigstuhl survey in the Southern Hemisphere are presented. I have searched for common proper motion companions to 173 field very low mass stars and brown dwarfs with spectral types > M5.0 V and magnitudes J less than or similar to 14.5 mag. I have measured for the first time the common proper motion of two new wide systems containing very low mass components, Konigstuhl 2 AB and 3 A-BC. Together with Konigstuhl 1 AB and 2M 0126-50 AB, they are among the widest systems in their respective classes (r = 450-11,900 AU). I have determined the minimum frequency of field wide multiples (r > 100 AU) with late-type components at 5.0% +/- 0.9% and the frequency of field wide late-type binaries with mass ratios q > 0.5 at 1.2% +/- 0: 9%. These values represent a key diagnostic of evolution history and low-mass star and brown dwarf formation scenarios. In addition, the proper motions of 62 field very low mass dwarfs are measured here for the first time.
引用
收藏
页码:520 / 526
页数:7
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