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Three newly-discovered M-dwarf companions of Solar Neighbourhood stars

J. Davy Kirkpatrick·James Liebert·K. L. Cruz·J. E. Gizis·I. Neill Reid
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Abstract

We present low-resolution spectroscopy of newly-discovered candidate companions to three stars in the Solar Neighbourhood. All three companions are M dwarfs, with spectral types ranging from M4 to M9.5. In two cases, G85-55`B' (M6) and G87-9`B' (M4), we have circumstantial evidence from spectroscopy, photometry and limited astrometry that the systems are physical binaries; in the third, G216-7B (M9.5), comparison of POSS II IIIaF plate material and the 2MASS image indicates common proper motion. The primary star in this system, G216-7A (M0), appears itself to be an unresolved, nearly equal-mass binary. All three low-mass companions are highly likely to be stellar in nature, although G216-7B lies very close to the hydrogen-burning limit.

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J. Davy Kirkpatrick, James Liebert, K. L. Cruz, J. E. Gizis, I. Neill Reid. 2001-04-08. Three newly-discovered M-dwarf companions of Solar Neighbourhood stars. https://doi.org/10.1086/322142

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