Swift J1357.2-0933 is a confirmed very faint black hole X-ray transient and has a short estimated orbital period of 2.8 h. We observed Swift J1357.2-0933 for...
Systematic Redshift of the Fe III UV Lines in Quasars: Measuring Supermassive Black Hole Masses under the Gravitational Redshift Hypothesis
We find that the Fe III λλ2039-2113 spectral feature in quasars appears systematically redshifted by amounts accountable under the hypothesis of gravitational...
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...
Testing the Jet Quenching Paradigm with an Ultradeep Observation of a Steadily Soft State Black Hole
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...
The accretion-ejection coupling in the black hole candidate X-ray binary MAXI J1836-194
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...
The black hole population in low-mass galaxies in large-scale cosmological simulations
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...
The complex evolution of the X-ray binary transient MAXI J1807+132 along the decay of its discovery outburst
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 and Interstellar Sight Line to GX 339-4
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...
The Faint "Heartbeats" of IGR J17091-3624: An Exceptional Black Hole Candidate
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...