# Radiative Processes and Geometry of Spectral States of Black-Hole Binaries

title={Radiative Processes and Geometry of Spectral States of Black-Hole Binaries},
author={Andrzej A. Zdziarski},
journal={arXiv: Astrophysics},
year={2000}
}
• A. Zdziarski
• Published 6 January 2000
• Physics
• arXiv: Astrophysics
I review radiative processes responsible for X-ray emission in the hard (low) and soft (high) spectral states of black-hole binaries. The main process in the hard state appears to be thermal Comptonization (in a hot plasma) of blackbody photons emitted by a cold disk. This is supported by correlations between the spectral index, the strength of Compton reflection, and the peak frequencies in the power density spectrum, as well as by the frequency-dependence of Fourier-resolved spectra. Spectral…

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