STOCHASTIC VARIABILITY IN X-RAY EMISSION FROM THE BLACK HOLE BINARY GRS 1915+105

Journal Article · Fri Jun 15 04:00:00 EDT 2012 · Astronomical Journal (New York, N.Y. Online)

DOI:https://doi.org/10.1088/0004-6256/143/6/148· OSTI ID:22034440

Polyakov, Yuriy S ^[1]; Neilsen, Joseph ^[2]

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1. USPolyResearch, Ashland, PA 17921 (United States)
2. MIT Kavli Institute for Astrophysics and Space Research, Cambridge, MA 02139 (United States)

We examine stochastic variability in the dynamics of X-ray emission from the black hole system GRS 1915+105, a strongly variable microquasar commonly used for studying relativistic jets and the physics of black hole accretion. The analysis of sample observations for 13 different states in both soft (low) and hard (high) energy bands is performed by flicker-noise spectroscopy (FNS), a phenomenological time series analysis method operating on structure functions and power spectrum estimates. We find the values of FNS parameters, including the Hurst exponent, flicker-noise parameter, and characteristic timescales, for each observation based on multiple 2500 s continuous data segments. We identify four modes of stochastic variability driven by dissipative processes that may be related to viscosity fluctuations in the accretion disk around the black hole: random (RN), power-law (1F), one-scale (1S), and two-scale (2S). The variability modes are generally the same in soft and hard energy bands of the same observation. We discuss the potential for future FNS studies of accreting black holes.

• OSTI ID: 22034440
• Journal Information: Astronomical Journal (New York, N.Y. Online), Journal Name: Astronomical Journal (New York, N.Y. Online) Journal Issue: 6 Vol. 143; ISSN 1538-3881
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ACCRETION DISKS
ASTRONOMY
ASTROPHYSICS
BLACK HOLES
DATA ANALYSIS
EMISSION SPECTRA
EMISSION SPECTROSCOPY
ENERGY SPECTRA
FLUCTUATIONS
JETS
NOISE
PHOTON EMISSION
RANDOMNESS
RELATIVISTIC RANGE
STOCHASTIC PROCESSES
STRUCTURE FUNCTIONS
TIME-SERIES ANALYSIS
X RADIATION