Effect of multiple Compton scattering on the temperature and emissioin spectra of accreting black holes

Journal Article · Mon Feb 01 04:00:00 EST 1982 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/159636· OSTI ID:5234970

Maraschi, L; Roasio, R; Treves, A

Spherical accretion onto a black hole with magnetic field dissipation is considered. For an optical depth close to 1, multiple Compton scattring is the dominant cooling mechanism near the hole. The effect is introduced in the energy balance equation using at each shell the spectral index, ..cap alpha.., of the Comptonized emission, derived from Monte Carlo calculations and analytic solutions of the Kompaneets equation, for homogeneous spheres with optical depths equivalent to that of the shell. In the inner region of the flow, the temperature obtained with this procedure differs significantly from that computed without taking into account Comptonization losses. In the cases examined-mass of the hole M = 10 M/sub circle-solid/ and M = 10/sup 8/ M/sub sun/; optical depths tau = 0.3--3, the resulting spectra are nearly power laws over a wide frequency range (10/sup 6/--10/sup 20/ Hz for the 10 M/sub sun/ case and 10/sup 13/-10/sup 20/ for the 10/sup 8/ Msun case) with 1< or approx. =..cap alpha..< or approx. =0.5. The spectral indexes have a much weaker dependence on tau than in the case of sources of fixed temperature.

• OSTI ID: 5234970
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 253:1; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640102* -- Astrophysics &amp; Cosmology-- Stars &amp; Quasi-Stellar
Radio &amp; X-Ray Sources
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ANALYTICAL SOLUTION
BASIC INTERACTIONS
BLACK HOLES
COMPTON EFFECT
COOLING
DISSIPATION FACTOR
ELASTIC SCATTERING
ELECTROMAGNETIC INTERACTIONS
EMISSION SPECTRA
ENERGY BALANCE
INTERACTIONS
MAGNETIC FIELDS
MONTE CARLO METHOD
OPACITY
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
PLASMA
SCATTERING
SPECTRA
STAR ACCRETION
STAR EVOLUTION