We examine the ability to test the black hole no-hair theorem at the 10% level in this decade using the binary black hole in OJ287. In the test we constrain the...

We present ultradeep radio observations with the Expanded Very Large Array of 4U 1957+11, a Galactic black hole (BH) candidate X-ray binary known to exist in a...

We present the results of our quasi-simultaneous radio, submm, infrared, optical and X-ray study of the Galactic black hole candidate X-ray binary MAXI J1836...

Recent systematic searches for massive black holes (BHs) in local dwarf galaxies led to the discovery of a population of faint active galactic nuclei (AGNs). We...

MAXI J1807+132 is an X-ray transient discovered during the decay of an outburst in 2017. We present optical and X-ray monitoring of the source over more than...

The distance to the black hole binary GX 339-4 remains a topic of debate. We examine high-resolution optical spectra of the Na D lines resolving the velocity...

We report on the first 180 days of Rossi X-Ray Timing Explorer observations of the outburst of the black hole candidate IGR J17091-3624. This source exhibits a...

We report the detection of an orbital period decay of dot{P}=-1.83+/- 0.66 ms yr-1 in the black hole X-ray binary XTE J1118+480. This corresponds to a period...

MWC 656 is the first known Be/black hole (BH) binary system. Be/BH binaries are important in the context of binary system evolution and sources of detectable...