We study the gas distribution in the recent merger remnant NGC 3656, a perturbed elliptical. The total gaseous mass content is a few times 10^9^M_sun_. The...

GD 552 is a high proper motion star with the strong, double-peaked emission lines characteristic of the dwarf nova class of cataclysmic variable (CV) star, and...

The optical/near-infrared (OIR) region of the spectra of low-mass X-ray binaries (XBs) appears to lie at the intersection of a variety of different emission...

We report on a detailed optical spectroscopic follow-up of the black hole (BH) transient MAXI J1820+070 (ASASSN-18ey). The observations cover the main part of...

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...

The advent of the new generation of X-ray telescopes yielded a significant step forward in our understanding of ionised absorption generated in the accretion...

We have identified a new intermediate polar, HS 0943+1404, as part of our ongoing search for cataclysmic variables in the Hamburg Quasar Survey. The orbital and...

We present a spectrophotometric study of short-term optical variability in the quiescent black hole X-ray transient V404 Cyg. This includes two nights of high...

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...