An unstable central disk in the superluminal black-hole X-ray binary GRS 1915+105
Abstract
We have analyzed the X-ray spectra of the microquasar GRS 1915+105, as observed with the PCA on the Rossi XTE, during periods of stable weak emission, outbursts and rapid flaring. We find that the complicated X-ray intensity curve of this source can be described by the rapid removal and replenishment of matter forming the inner part of an optically thick accretion disk, probably caused by a thermal-viscous instability analogous to that operating in dwarf novae, but here driven by the Lightman-Eardley instability. We find that the mass accretion rate in quiescence is 10^-6 solar masses per year. Only a small fraction of the energy liberated by accretion is emitted as radiation. We suggest that most of this energy is advected into the black hole in the high-viscosity state of the outburst cycle.
Cite
@article{arxiv.astro-ph/9702048,
title = {An unstable central disk in the superluminal black-hole X-ray binary GRS 1915+105},
author = {T. Belloni and M. Mendez and A. R. King and M. van der Klis and J. van Paradijs},
journal= {arXiv preprint arXiv:astro-ph/9702048},
year = {2009}
}
Comments
8 pages, 2 PS figures