Radiative processes, spectral states and variability of black-hole binaries

Zdziarski, A.A.; Gierlinski, M.

Abstract

We review radiative processes responsible for X-ray emission in hard(low) and soft (high) spectral states of black-hole binaries. The main process in the hard state appears to be scattering of blackbody photons from a cold disk by thermal electrons in a hot inner flow, and any contribution from nonthermal synchrotron emission is at most small. In the soft states, blackbody disk emission dominates energetically, and its high-energy tail is due to scattering by hybrid, thermal/nonthermal electrons, probably in active regions above the disk surface. State transitions appear to correspond to a variable inner radius of the cold disk driven by changes of the accretion rate. The existence of two accretion solutions, hot and cold, in a range of the accretion rate leads to hysteresis in low-mass X-ray binaries.

Citation

Zdziarski, A., & Gierlinski, M. (2004). Radiative processes, spectral states and variability of black-hole binaries. Progress of theoretical physics. Supplement, 155, 99-119

• Journal Article Type: Article
• Publication Date: 2004
• Deposit Date: Dec 19, 2006
• Journal: Progress of theoretical physics. Supplement.
• Print ISSN: 0375-9687
• Publisher: Oxford University Press
• Peer Reviewed: Not Peer Reviewed
• Volume: 155
• Pages: 99-119
• Keywords: Advection-dominated accretion, High-energy spectra, X-ray-emission, Cygnus X-1, Radio galaxies, Line, Nova-muscae-1991, Comptonization, Variability, Reflection.
• Public URL: https://durham-repository.worktribe.com/output/1584858
• Publisher URL: http://ptp.ipap.jp/link?PTPS/155/99