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Title: Spin and Accretion Rate Dependence of Black Hole X-Ray Spectra
Abstract We present a survey of how the spectral features of black hole X-ray binary systems depend on spin, accretion rate, viewing angle, and Fe abundance when predicted on the basis of first-principles physical calculations. The power-law component hardens with increasing spin. The thermal component strengthens with increasing accretion rate. The Compton bump is enhanced by higher accretion rate and lower spin. The Fe K α equivalent width grows sublinearly with Fe abundance. Strikingly, the K α profile is more sensitive to accretion rate than to spin because its radial surface brightness profile is relatively flat, and higher accretion rate extends the production region to smaller radii. The overall radiative efficiency is at least 30%–100% greater than as predicted by the Novikov–Thorne model.  more » « less
Award ID(s):
1715032 2009260 1707826
PAR ID:
10309237
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
922
Issue:
2
ISSN:
0004-637X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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