STOCHASTIC VARIABILITY IN X-RAY EMISSION FROM THE BLACK HOLE BINARY GRS 1915+105
Author(s)Polyakov, Yuriy S.; Timashev, Serge F.; Neilsen, Joseph M. G.
MetadataShow full item record
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.
DepartmentMIT Kavli Institute for Astrophysics and Space Research
The Astronomical Journal
Polyakov, Yuriy S., Joseph Neilsen, and Serge F. Timashev. “STOCHASTIC VARIABILITY IN X-RAY EMISSION FROM THE BLACK HOLE BINARY GRS 1915+105.” The Astronomical Journal 143, no. 6 (May 14, 2012): 148. © 2012 The American Astronomical Society
Final published version