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The Spin of the Near-Extreme Kerr Black Hole GRS 1915+105
Based on a spectral analysis of the X-ray continuum that employs a fully relativistic accretion disk model, we conclude that the compact primary of the binary X-ray source GRS 1915+105 is a rapidlyExpand
SUSTAINED MAGNETOROTATIONAL TURBULENCE IN LOCAL SIMULATIONS OF STRATIFIED DISKS WITH ZERO NET MAGNETIC FLUX
We examine the effects of density stratification on magnetohydrodynamic turbulence driven by the magnetorotational instability in local simulations that adopt the shearing box approximation. OurExpand
THE RADIATIVE EFFICIENCY OF ACCRETION FLOWS IN INDIVIDUAL ACTIVE GALACTIC NUCLEI
The radiative efficiency of AGN is commonly estimated based on the total mass accreted and the total AGN light emitted per unit volume in the universe integrated over time (the Soltan argument). InExpand
Relativistic Accretion Disk Models of High-State Black Hole X-Ray Binary Spectra
We present calculations of non-LTE, relativistic accretion disk models applicable to the high/soft state of black hole X-ray binaries. We include the effects of thermal Comptonization and bound-freeExpand
Estimating the Spin of Stellar-Mass Black Holes by Spectral Fitting of the X-Ray Continuum
We fit X-ray spectral data in the thermal-dominant, or high-soft, state of two dynamically confirmed black holes, GRO J1655-40 and 4U 1543-47, and estimate the dimensionless spin parameters a* ≡ a/MExpand
Intrinsic disc emission and the soft X‐ray excess in active galactic nuclei
Narrow-line Seyfert 1 (NLS1) galaxies have low-mass black holes and mass accretion rates close to (or exceeding) Eddington, so a standard blackbody accretion disc should peak in the extremeExpand
A Global Three Dimensional Radiation Magneto-hydrodynamic Simulation of Super-Eddington Accretion Disks
We study super-Eddington accretion flows onto black holes using a global three dimensional radiation magneto-hydrodynamical simulation. We solve the time dependent radiative transfer equation for theExpand
The Extreme Spin of the Black Hole in Cygnus X-1
The compact primary in the X-ray binary Cygnus X-1 was the first black hole to be established via dynamical observations. We have recently determined accurate values for its mass and distance, andExpand
The UV Continuum of Quasars: Models and SDSS Spectral Slopes
We measure long (2200-4000 A) and short (1450-2200 A) wavelength spectral slopes α (Fν να) for quasar spectra from the Sloan Digital Sky Survey. The long- and short-wavelength slopes are computedExpand
Testing Accretion Disk Theory in Black Hole X-Ray Binaries
WepresentresultsfromspectralmodelingofthreeblackholeX-raybinaries:LMCX-3,GROJ1655� 40,andXTE J1550� 564. Using a sample of disk-dominated observations, we fit the data with a range of spectral modelsExpand
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