We present a novel strategy to uncover the Galactic population of quiescent black holes (BHs). This is based on a new concept, the photometric mass function...

Using simultaneous observations in X-rays and optical, we have performed a homogeneous analysis of the cross-correlation behaviours of four X-ray binaries...

Our simultaneous three-colour (BVR) polarimetric observations of the low-mass black hole X-ray binary V404 Cyg show a small but statistically significant change...

Context. LB-1 (alias ALS 8775) has been proposed as either an X-ray dim B-type star plus black hole (B+BH) binary or a Be star plus an inflated stripped star...

Swift J1357.2−0933 is a transient low-mass X-ray binary hosting a stellar-mass black hole. The source exhibits optical dips and very broad emission lines during...

The INTEGRAL/EINSTEIN/ROSAT/NVSS objects IGR J17418-12122, 2E 1739.1-1210, 1RXS J174155.3-121157 and NVSS J174155-121201 have recently been suggested to be the...

Following the discovery of the new X-ray transient XTE J1637-498 (Atel #1699), we obtained a short (nearly 1 ksec) observation using the Swift/XRT in PC mode on...

We have obtained intermediate resolution optical spectra of the black-hole candidate Nova Sco 1994 in June 1996, when the source was in an X-ray/optical active...