Authors:
Harlaftis E.T., Dhillon V.S., Castro-Tirado A.
Journal:
Astronomy and Astrophysics
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 He II emission at 2.189 μm 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 GRS 1915+105 or Sco X-1.
Keywords:
Black hole physics; Infrared: stars; Stars: binaries; Stars: individual: GRS 1915+105; X-ray: stars