Three newly discovered M-dwarf companions of solar neighborhood stars

Citation
Jd. Kirkpatrick et al., Three newly discovered M-dwarf companions of solar neighborhood stars, PUB AST S P, 113(785), 2001, pp. 814-820
Citations number
23
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Space Sciences
Journal title
PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC
ISSN journal
0004-6280 → ACNP
Volume
113
Issue
785
Year of publication
2001
Pages
814 - 820
Database
ISI
SICI code
0004-6280(200107)113:785<814:TNDMCO>2.0.ZU;2-6
Abstract
We present low-resolution spectroscopy of newly discovered candidate compan ions to three stars in the solar neighborhood. All three companions are M d warfs, with spectral types ranging from M4 to M9.5. In two cases, G85-55B ( M6) and G87-9B (M4), we have circumstantial evidence from spectroscopy, pho tometry, and limited astrometry that the systems are physical binaries; in the third, G216-7B (M9.5), comparison of POSS II IIIaF plate material and t he 2MASS image indicates common proper motion. The primary star in this sys tem, G216-7A (M0), is itself an unresolved, nearly equal-mass binary. All t hree low-mass companions are highly likely to be stellar in nature, althoug h G216-7B lies very close to the hydrogen-burning limit.