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The fundamental plane of accretion onto black holes with dynamical masses
Black hole accretion and jet production are areas of intensive study in astrophysics. Recent work has found a relation between radio luminosity, X-ray luminosity, and black hole mass. With the
A REVERBERATION-BASED MASS FOR THE CENTRAL BLACK HOLE IN NGC 4151
We have undertaken a new ground-based monitoring campaign to improve the estimates of the mass of the central black hole in NGC 4151. We measure the lag time of the broad H? line response compared to
X-ray reverberation around accreting black holes
Luminous accreting stellar mass and supermassive black holes produce power–law continuum X-ray emission from a compact central corona. Reverberation time lags occur due to light travel time delays
Measuring the spin of GRS 1915+105 with relativistic disk reflection
GRS 1915+105 harbors one of the most massive known stellar black holes in the Galaxy. In 2007 May, we observed GRS 1915+105 for ∼117 ks in the low/hard state using Suzaku. We collected and analyzed
The Hot and Energetic Universe: A White Paper presenting the science theme motivating the Athena+ mission
This White Paper, submitted to the recent ESA call for science themes to define its future large missions, advocates the need for a transformational leap in our understanding of two key questions in
Testing thermal reprocessing in active galactic nuclei accretion discs
The thermal reprocessing hypothesis in active galactic nuclei (AGN), where extreme ultraviolet/X-ray photons are reprocessed by the accretion disc into optical/UV photons, predicts
NGC 5548 in a Low-Luminosity State: Implications for the Broad-Line Region
We describe results from a new ground-based monitoring campaign on NGC 5548, the best-studied reverberation-mapped AGN. We find that it was in the lowest luminosity state yet recorded during a
RELATIVISTIC LINES AND REFLECTION FROM THE INNER ACCRETION DISKS AROUND NEUTRON STARS
A number of neutron star low-mass X-ray binaries (LMXBs) have recently been discovered to show broad, asymmetric Fe K emission lines in their X-ray spectra. These lines are generally thought to be
Discovery of a relation between black hole mass and soft X-ray time lags in active galactic nuclei
We carried out a systematic analysis of time lags between X-ray energy bands in a large sample (32 sources) of unabsorbed, radio quiet active galactic nuclei (AGN), observed by XMM-Newton. The
Modelling the broad Fe Kα reverberation in the AGN NGC 4151
The recent detection of X-ray reverberation lags, especially in the Fe Kα line region, around active galactic nuclei (AGN) has opened up the possibility of studying the time-resolved response
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