The Double Infrared Source Toward the Soft Gamma-Ray Repeater SGR 1900+14
Vrba, F. J., Luginbuhl, C. B., Hurley, K. C., Li, P., Kulkarni, S. R.,
Van Kerkwijk, M. H., Hartmann, D. H., Campusano, L. E., Graham, M. J.,
Clowes, R. G., Kouveliotou, C., Probst, R., Gatley, I., Merrill, M.,
Joyce, R., Mendez, R., Smith, I., & Schultz, A.
We report the results of an extensive set of optical and near-infrared
photometry and spectroscopy of the double infrared source reported by
Hartmann et al. (1995) as a potential counterpart for the Galactic soft
gamma-ray repeater SGR 1900+14.
These objects are found to be variable but otherwise normal M5 supergiant
stars at a distance of approximately 12-15 kpc and extinguished by A_V
approx 19.2 mag, primarily by the general interstellar medium.
We argue that the supergiants are likely gravitationally bound.
These stars are positionally coincident with both quiescent X-ray and
IRAS sources, suggestive of a yet-undetected third component to the
system which may be responsible for the SGR.
Status:
1996, ApJ, 468, 225.
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