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IR spectra of the microquasar GRS 1915+105 during a low state

E. T. Harlaftis·V. R. Dhillon·A. Castro-Tirado
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Abstract

There is controversy regarding the nature of the suspected donor star to the microquasar GRS 1915+105, and hence whether GRS 1915+105 is a high mass X-ray binary (HMXB) or a low-mass X-ray binary (LMXB). In order to clarify this issue, we obtained an infrared (J, H and K) spectrum of GRS 1915+105 in its low state which shows a steeper continuum than the prototype X-ray binary Sco X-1. We did not detect any HeII emission at 2.189 microns from GRS 1915+105 in our quiescent spectrum, indicating that the line is transient and is only observed during episodes of high X-ray activity. For our instrument configuration, there is no detection of the 12CO lines which are characteristic of late-type stars either in GRS1915+105 or Sco X-1.

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E. T. Harlaftis, V. R. Dhillon, A. Castro-Tirado. 2001-01-22. IR spectra of the microquasar GRS 1915+105 during a low state. https://doi.org/10.1051/0004-6361%3A20010110

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