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Title: A high-frequency Doppler feature in the power spectra of simulated GRMHD black hole accretion disks

Abstract

Black hole binaries exhibit a wide range of variability phenomena, from large-scale state changes to broadband noise and quasi-periodic oscillations, but the physical nature of much of this variability is poorly understood. We examine the variability properties of three GRMHD simulations of thin accretion disks around black holes of varying spin, producing light curves and power spectra as would be seen by observers. We find that the simulated power spectra show a broad feature at high frequency, which increases in amplitude with the inclination of the observer. We show that this high-frequency feature is a product of the Doppler effect and that its location is a function of the mass and spin of the black hole. This Doppler feature demonstrates that power spectral properties of the accretion disk can be tied to, and potentially used to determine, physical properties of the black hole.

Authors:
; ; ;  [1];  [2]
  1. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA (United States)
  2. Astronomy Department, University of Arizona, 933 North Cherry Avenue, Tucson, AZ (United States)
Publication Date:
OSTI Identifier:
22357068
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 785; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCRETION DISKS; AMPLITUDES; BLACK HOLES; COMPUTERIZED SIMULATION; DOPPLER EFFECT; INCLINATION; MAGNETOHYDRODYNAMICS; MASS; NOISE; OSCILLATIONS; PERIODICITY; PHYSICAL PROPERTIES; SPECTRA; SPIN; VISIBLE RADIATION; X RADIATION

Citation Formats

Wellons, Sarah, Zhu, Yucong, Narayan, Ramesh, McClintock, Jeffrey E., and Psaltis, Dimitrios, E-mail: swellons@cfa.harvard.edu. A high-frequency Doppler feature in the power spectra of simulated GRMHD black hole accretion disks. United States: N. p., 2014. Web. doi:10.1088/0004-637X/785/2/142.
Wellons, Sarah, Zhu, Yucong, Narayan, Ramesh, McClintock, Jeffrey E., & Psaltis, Dimitrios, E-mail: swellons@cfa.harvard.edu. A high-frequency Doppler feature in the power spectra of simulated GRMHD black hole accretion disks. United States. doi:10.1088/0004-637X/785/2/142.
Wellons, Sarah, Zhu, Yucong, Narayan, Ramesh, McClintock, Jeffrey E., and Psaltis, Dimitrios, E-mail: swellons@cfa.harvard.edu. 2014. "A high-frequency Doppler feature in the power spectra of simulated GRMHD black hole accretion disks". United States. doi:10.1088/0004-637X/785/2/142.
@article{osti_22357068,
title = {A high-frequency Doppler feature in the power spectra of simulated GRMHD black hole accretion disks},
author = {Wellons, Sarah and Zhu, Yucong and Narayan, Ramesh and McClintock, Jeffrey E. and Psaltis, Dimitrios, E-mail: swellons@cfa.harvard.edu},
abstractNote = {Black hole binaries exhibit a wide range of variability phenomena, from large-scale state changes to broadband noise and quasi-periodic oscillations, but the physical nature of much of this variability is poorly understood. We examine the variability properties of three GRMHD simulations of thin accretion disks around black holes of varying spin, producing light curves and power spectra as would be seen by observers. We find that the simulated power spectra show a broad feature at high frequency, which increases in amplitude with the inclination of the observer. We show that this high-frequency feature is a product of the Doppler effect and that its location is a function of the mass and spin of the black hole. This Doppler feature demonstrates that power spectral properties of the accretion disk can be tied to, and potentially used to determine, physical properties of the black hole.},
doi = {10.1088/0004-637X/785/2/142},
journal = {Astrophysical Journal},
number = 2,
volume = 785,
place = {United States},
year = 2014,
month = 4
}
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