Speaker
Description
The black hole X-ray binary Cygnus X-1 exhibits high levels of variability spanning many decades in frequency across all of its spectral states. This broad band variability power is comprised of several distinct components evolving in concert as the source changes states. The amplitudes, frequencies, and energy dependent lags of these components reveal information about the physical accretion processes which give rise to them. To reveal these components and understand their evolution, we model 14 years of Rossi X-ray Timing Explorer observations of Cygnus X-1. We consider the appearance and disappearance of these components, their contribution to the observed time lags, and assess their degree of independence. As opposed to most previous studies, we consider lag properties, and their dependence upon spectral properties, decomposed into distinct variability components. In doing so, we get a fuller picture of the spectral-timing correlations in this source across multiple failed and successful spectral state transitions.