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The Infrared Counterpart of the Microquasar GRS 1758-258

D. M. Rothstein·S. S. Eikenberry·S. Chatterjee·E. Egami·S. G. Djorgovski·W. A. Heindl
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Abstract

We present revised infrared (2.2 micron) astrometry of the field containing the Galactic microquasar GRS 1758-258, using observations at the Keck I 10-m telescope. We find three candidates for the microquasar within a 3 sigma error circle, but none within 2 sigma. We show that if the 18.4 day X-ray period of GRS 1758-258 is due to a binary orbit, then only one of the three candidates, an early K-type giant, is large enough to power the microquasar via Roche lobe overflow. We therefore identify this star as the infrared counterpart of GRS 1758-258, which we classify as a low mass X-ray binary. Long term infrared monitoring of this source should provide further information about the microquasar system, including a confirmation of the X-ray period and an estimate of the compact object's mass.

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D. M. Rothstein, S. S. Eikenberry, S. Chatterjee, E. Egami, S. G. Djorgovski, W. A. Heindl. 2002-10-15. The Infrared Counterpart of the Microquasar GRS 1758-258. https://doi.org/10.1086/345546

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