Stochastic variability in X-ray emission from the black hole binary grs 1915+105

Yuriy S. Polyakov, Joseph Neilsen, Serge F. Timashev

Research output: Contribution to journalArticlepeer-review

6 Scopus citations

Abstract

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.

Original languageEnglish (US)
JournalAstronomical Journal
Volume143
Issue number6
DOIs
StatePublished - Jun 2012
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science

Keywords

  • X-rays: individual (GRS 1915+105)
  • accretion
  • accretion disks
  • binaries: close
  • black hole physics
  • methods: data analysis
  • methods: statistical

Fingerprint

Dive into the research topics of 'Stochastic variability in X-ray emission from the black hole binary grs 1915+105'. Together they form a unique fingerprint.

Cite this