ar X iv : a st ro - p h / 95 02 03 8 v 1 7 F eb 1 99 5 A Luminous Companion to SGR 1806 − 20 1
نویسندگان
چکیده
We have obtained infrared spectra of the star suggested to be the counterpart of the soft γ-ray repeater (SGR) 1806−20. We found strong emission lines similar to those seen in the spectra of the rare Luminous Blue Variables and B[e] stars. A He I absorption line is also seen, from which we infer a spectral type O9–B2. This classification, in combination with the minimum distance of ∼ > 6 kpc inferred from its extinction, makes the star one of the most luminous in the Galaxy. We infer that it is a companion to SGR 1806−20, and suggest that the presence of a companion is somehow related to the SGR phenomenon. 1 This is a preprint of a paper submitted to The Astrophysical Journal (Letters). No bibliographic reference should be made to this preprint. Permission to cite material in this paper must be received from the authors.
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