Infrared Spectroscopy of GX 1+4/V2116 Oph: Evidence for a Fast Red Giant Wind?

Deepto Chakrabarty; Marten H. van Kerkwijk; James E. Larkin

doi:10.1086/311271

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arXiv · astro-ph/9802137

Infrared Spectroscopy of GX 1+4/V2116 Oph: Evidence for a Fast Red Giant Wind?

Deepto Chakrabarty·Marten H. van Kerkwijk·James E. Larkin

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Abstract

We present infrared spectroscopy of the low-mass X-ray binary GX 1+4/V2116 Oph. This symbiotic binary consists of a 2-min accretion-powered pulsar and an M5 III red giant. A strong He I 1.083 micron emission line with a pronounced P Cygni profile was observed. From the blue edge of this feature, we infer an outflow velocity of 250(50) km/s. This is an order of magnitude faster than a typical red giant wind, and we suggest that radiation from the accretion disk or the neutron star may contribute to the acceleration of the outflow. We infer a wind mass loss rate of around 10^-6 Msun/yr. Accretion from such a strong stellar wind provides a plausible alternative to Roche lobe overflow for supplying the accretion disk which powers the X-ray source. The H I Paschen beta and He I 1.083 micron lines showed no evidence for the dramatic changes previously reported in some optical lines, and no evidence for pulsations at the 2-min pulsar period.

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Deepto Chakrabarty, Marten H. van Kerkwijk, James E. Larkin. 1998-02-11. Infrared Spectroscopy of GX 1+4/V2116 Oph: Evidence for a Fast Red Giant Wind?. https://doi.org/10.1086/311271

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