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The optical emission lines as a probe of state transitions in black-hole candidates

Roberto Soria
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Abstract

Optical spectroscopic studies of emission lines in black-hole candidates can help us investigate state transitions in those systems. Changes in the optical line profiles reflect changes in the geometry of the accretion flow, usually associated with X-ray state transitions in the inner region. We identify at least four optical states in the black-hole candidate GRO J1655-40 in outburst, and two optical states in GX339-4.

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Roberto Soria. 2001-01-17. The optical emission lines as a probe of state transitions in black-hole candidates. https://doi.org/10.1142/9789812777386_0547

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