ABSTRACT We use the anomalous-diffusion interpolation and parameterization procedure developed within the framework of flicker-noise spectroscopy (FNS) to characterize the stochastic variability of X-ray emission from accreting black hole GRS 1915+105. Our analysis of the lightcurves with a sampling frequency of 16 Hz in soft and hard X-ray energy bands shows that the stochastic variability of soft-band lightcurves is mostly subdiffusive while the hard X-ray emission is characterized primarily by fractional Gaussian noise. The comparison of FNS parameters between the soft and hard energy bands (corresponding roughly to different X-ray emission mechanisms) implies that hard X-rays have more relative variability at higher frequencies and are characterized by shorter diffusion timescales than soft X-rays. We suggest that the differences in the stochastic variabilities may be attributed to changes in either the viscosity law in the accretion disk or the geometry of the accretion flow.
Serge Timashev hasn't uploaded this paper.
Let Serge know you want this paper to be uploaded.
