The central engines of active galactic nuclei (AGNs) are powered by accreting supermassive
black holes, and while AGNs are known to play an important role in galaxy evolution, the key …

Relativistic reflection features are commonly observed in the X-ray spectra of accreting black
holes. In the presence of high quality data and with the correct astrophysical model, X-ray …

We present the first extensive radio to γ-ray observations of a fast-rising blue optical
transient, AT 2018cow, over its first∼ 100 days. AT 2018cow rose over a few days to a peak …

Accreting black holes emit highly collimated radio jets expanding at speeds approaching
light speed. Some of these jets appear to be expanding at superluminal speeds due to …

We extend our recent work on black hole spin in X-ray binary systems to include an analysis
of 189 archival NuSTAR observations from 24 sources. Using self-consistent data reduction …

The launch of NuSTAR and the increasing number of binary black hole (BBH) mergers
detected through gravitational wave observations have exponentially advanced our …

Current models of the spectrum of X-rays reflected from accretion discs around black holes
and other compact objects are commonly calculated assuming that the density of the disc …

We report on a comprehensive analysis of simultaneous X-ray polarimetric and spectral data
of the bright atoll source GX 9+ 9 with the Imaging X-ray Polarimetry Explorer (IXPE) and …

Aims. The only relativistic reflection model that implements a parameter relating the intensity
incident on an accretion disk to the observed intensity is relxill. The parameter used in …

We analyze simultaneously six composite RXTE spectra of GX 339–4 in the hard state
comprising 77 million counts collected over 196 ks. The source spectra are ordered by …