Two nearby M dwarf binaries from the Two Micron All Sky Survey

被引：43

作者：

Gizis, JE ^{[1
]}

Monet, DG

Reid, IN

Kirkpatrick, JD

Burgasser, AJ

机构：

[1] Univ Massachusetts, Dept Phys & Astron, Amherst, MA 01003 USA

[2] USN Observ, Flagstaff, AZ 86002 USA

[3] Univ Penn, Dept Phys & Astron, Philadelphia, PA 19104 USA

[4] CALTECH, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA

[5] CALTECH, Dept Phys, Pasadena, CA 91125 USA

来源：

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY | 2000年 / 311卷 / 02期

关键词：

binaries : general; stars; low-mass; brown dwarfs; solar neighbourhood; infrared : stars;

D O I：

10.1046/j.1365-8711.2000.03060.x

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We report the discovery of two binary M dwarf systems in the immediate solar neighbourhood using the Two Micron All Sky Survey (2MASS). The first is an M6.5 companion to the nearby G star HD 86728 (Gl 376). The known properties of HD 86728 indicate that the M dwarf (Gl 376B) is old, metal-rich and only 14.9 parsec away. The M dwarf is highly active, with both H alpha and X-ray emission. Thus, Gl 376B offers the opportunity to study an old, bright, active M dwarf with known metallicity, age and luminosity. We show that it is probable that Gl 376B is itself an unresolved pair. The other system consists of an M6.5 and an M8 dwarf with 14.5 arcsec separation. We estimate a distance of similar to 16 parsec for this very low-mass pair. Stronger activity is observed in the M6.5 dwarf, supporting evidence that chromospheric activity is weakening near the hydrogen-burning limit.

引用

页码：385 / 388

页数：4

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