James F. Steiner

Self-consistent Black Hole Accretion Spectral Models and the Forgotten Role of Coronal Comptonization of Reflection Emission

Continuum and reflection spectral models have each been widely employed in measuring the spins of accreting black holes. However, the two approaches have not been implemented together in a photon-conserving, self-consistent framework. We develop such a framework using the black hole X-ray binary GX 339–4 as a touchstone source, and we demonstrate three important ramifications. (1) Compton scattering of reflection emission in the corona is routinely ignored, but is an essential consideration given that reflection is linked to the regimes with strongest Comptonization. Properly accounting for this causes the inferred reflection fraction to increase substantially, especially for the hard state. Another important impact of the Comptonization of reflection emission by the corona is the downscattered tail. Downscattering has the potential to mimic the relativistically broadened red wing of the Fe line associated with a spinning black hole. (2) Recent evidence for a reflection component with a harder spectral index than the power-law continuum is naturally explained as Compton-scattered reflection emission. (3) Photon conservation provides an important constraint on the hard states accretion rate. For bright hard states, we show that disk truncation to large scales R » R_(ISCO) is unlikely as this would require accretion rates far in excess of the observed Ṁ of the brightest soft states. Our principal conclusion is that when modeling relativistically broadened reflection, spectral models should allow for coronal Compton scattering of the reflection features, and when possible, take advantage of the additional constraining power from linking to the thermal disk component.

Testing the Performance and Accuracy of the RELXILL Model for the Relativistic X-Ray Reflection from Accretion Disks

The reflection spectroscopic model RELXILL is commonly implemented in studying relativistic X-ray reflection from accretion disks around black holes. We present a systematic study of the models capability to constrain the dimensionless spin and ionization parameters from

Reflection Spectroscopy of the Black Hole Binary XTE J1752-223 in its Long-Stable Hard State

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STRONGER REFLECTION FROM BLACK HOLE ACCRETION DISKS IN SOFT X-RAY STATES

6,000 NuSTAR simulations of a bright X-ray source employing the lamppost geometry. We employ high count spectra to show the limitations in the model without being confused with limitations in signal-to-noise. We find that both parameters are well-recovered at 90% confidence with improving constraints at higher reflection fraction, high spin, and low source height. We test spectra across a broad range - first at 10

The effects of high density on the X-ray spectrum reflected from accretion discs around black holes

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Estimating The Spin Of The Stellar-Mass Black Hole XTE J1550-564

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Black-hole spin measurement via X-ray continuum spectroscopy

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A Refined Black Hole Mass for the X-ray Transient GRS 1009-45

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The Spin-Jet Connection for XTE J1550-564

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On The Stable Inner-disk Radius Of BH LMC X-3

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