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Title: Shapes of Fe K{sub {alpha}} lines from annuli near black holes

Abstract

Recent x-ray observations of microquasars and Seyfert galaxies reveal broad emission lines in their spectra, which can arise in the innermost parts of accretion disks. We consider a radiating annulus model to simulate spectral line shapes. That is a natural approximation for narrow emitting circular rings without extra astrophysical assumptions about emissivity laws. Recently, Mueller and Camenzind (Astron. Astrophys. 413, 861 (2004)) presented results of their calculations and classified different types of spectral line shapes and described their origin. We clarified their hypothesis about an origin of double peaked and double horned line shapes. On the basis of results of numerical simulations, we showed that double peaked spectral lines arise almost for any locations of narrow emission rings (annuli), although Mueller and Camenzind claimed that such profiles arise for relatively flat spacetimes and typical radii for emission region of about 25r{sub g}. We showed that triangular spectral lines could arise for nearest annuli and high inclination angles. We discuss a possibility of appearance of narrow spectral line shapes as a result of spiraling evolution of matter along quasi-circular orbits which could be approximated by narrow annuli.

Authors:
 [1]
  1. National Astronomical Observatories of Chinese Academy of Sciences (China), E-mail: zakharov@itep.ru
Publication Date:
OSTI Identifier:
21075957
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Atomic Nuclei; Journal Volume: 70; Journal Issue: 1; Other Information: DOI: 10.1134/S106377880701019X; Copyright (c) 2007 Nauka/Interperiodica; Article Copyright (c) 2007 Pleiades Publishing, Ltd; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ACCRETION DISKS; APPROXIMATIONS; ASTRON; ASTROPHYSICS; BLACK HOLES; EMISSION; EMISSIVITY; HYPOTHESIS; IRON; QUASARS; SEYFERT GALAXIES; SIMULATION; SPACE-TIME; SPECTRA; X RADIATION

Citation Formats

Zakharov, A. F. Shapes of Fe K{sub {alpha}} lines from annuli near black holes. United States: N. p., 2007. Web. doi:10.1134/S106377880701019X.
Zakharov, A. F. Shapes of Fe K{sub {alpha}} lines from annuli near black holes. United States. doi:10.1134/S106377880701019X.
Zakharov, A. F. Mon . "Shapes of Fe K{sub {alpha}} lines from annuli near black holes". United States. doi:10.1134/S106377880701019X.
@article{osti_21075957,
title = {Shapes of Fe K{sub {alpha}} lines from annuli near black holes},
author = {Zakharov, A. F.},
abstractNote = {Recent x-ray observations of microquasars and Seyfert galaxies reveal broad emission lines in their spectra, which can arise in the innermost parts of accretion disks. We consider a radiating annulus model to simulate spectral line shapes. That is a natural approximation for narrow emitting circular rings without extra astrophysical assumptions about emissivity laws. Recently, Mueller and Camenzind (Astron. Astrophys. 413, 861 (2004)) presented results of their calculations and classified different types of spectral line shapes and described their origin. We clarified their hypothesis about an origin of double peaked and double horned line shapes. On the basis of results of numerical simulations, we showed that double peaked spectral lines arise almost for any locations of narrow emission rings (annuli), although Mueller and Camenzind claimed that such profiles arise for relatively flat spacetimes and typical radii for emission region of about 25r{sub g}. We showed that triangular spectral lines could arise for nearest annuli and high inclination angles. We discuss a possibility of appearance of narrow spectral line shapes as a result of spiraling evolution of matter along quasi-circular orbits which could be approximated by narrow annuli.},
doi = {10.1134/S106377880701019X},
journal = {Physics of Atomic Nuclei},
number = 1,
volume = 70,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}
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