出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：X-ray spectral variability is a powerful probe of the relationship between the accretion disc and
corona in accreting black holes. To date most efforts have concentrated on the relationship
between reflection (iron line and continuum) and the X-ray power law, whilst the accompanying
thermal reprocessing has been largely neglected. We have started a program to use rms spectra
and a new analysis technique, the "covariance spectrum" to disentangle the different
components of the X-ray spectra of black hole X-ray binaries, identify the relationship between
disc thermal emission and the illuminating power law and place strong constraints on the
geometry of the disc and corona. Here we present the first results from this study which show
evidence for a fluctuating inner disc truncation radius in the hard states of SWIFT J1753.5-0127
and GX 339-4.
