2004/01/01 by A. A. Zdziarski, Andrzej A. Zdziarski, Marek Gierliński +1 · 1 citation
Earth and Planetary Sciences · Engineering · Physics and Astronomy · #Accretion (finance) #Astrophysical Phenomena and Observations #Astrophysics #Black-body radiation #Electron #High-pressure geophysics and materials #Mechanics and Biomechanics Studies #Nuclear physics #Optics #Photon #Physics #RADIUS #Radiation #Radiative transfer #Scattering #Thermal #astro-ph
paper · pdf · doi:10.1143/ptps.155.99
published as Prog.Theor.Phys.Suppl.155:99-119,2004 · Proceedings of "Stellar-mass, intermediate-mass, and supermassive black holes", Kyoto, 10.2003
crossref issued 2004/01/01 · crossref published 2004/01/01 · crossref published-print 2004/01/01 · openalex publication_date 2004/01/01 · arxiv created 2004/12/06 · crossref created 2007/06/30 · arxiv updated 2009/12/01 · crossref deposited 2017/08/24 · openalex created_date 2020/11/23 · crossref indexed 2026/08/06 · openalex updated_date 2026/08/08
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.