Disentangling the disks in hard state black hole X-ray binaries

We propose up to 3 TOO EPICpn observations of the hard states of the BHXRBs CygX1, GX 3394 and SWIFT J1753.50127, to be triggered by a significant change intheir timing signatures with respect to those seen in earlier hard stateobservations. In this way, we will confirm or disprove the standard picture ofthe hard state where correlated timing and spectral properties are caused bytruncation of the accretion disk. We will use rmsspectra to disentangle theintrinsic and reprocessed contributions to disk thermal emission, and determinewhether the enhanced disk variability seen on longer timescales is associatedwith the lowfrequency Lorentzian in the PSD, which would for the first timeidentify this key timing signature with the disk. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]