Related papers: A Simple Comptonization Model
We present numerical spectral and vertical structure calculations appropriate for near-Eddington-luminosity, radiation-pressure-dominated accretion disks around stellar-mass black holes. We cover a wide range of black hole spins and…
We present a full set of model atmosphere equations for the accretion disk around a supermassive black hole irradiated by hard X-ray lamp of power-law spectral distribution. Model equations allow for multiple Compton scattering of radiation…
Resonant inelastic X-ray scattering (RIXS) is used increasingly for characterizing low-energy collective excitations in materials. RIXS is a powerful probe, which often requires sophisticated theoretical descriptions to interpret the data.…
Energetic X-ray radiations emitted from various accretion systems are widely considered to be produced by Comptonization in the hot corona. The corona and its interaction with the disc play an essential role in the evolution of the system…
We present a survey of how the spectral features of black hole X-ray binary systems depend on spin, accretion rate, viewing angle, and Fe abundance when predicted on the basis of first principles physical calculations. The power law…
The soft X-ray excess in the spectra of active galactic nuclei is characterized by similar electron temperatures of 0.1 -- 0.3 keV and similar photon indices around 2.2 -- 3, if fitted with inverse Comptonization. It remains a puzzle why…
The X-ray spectra of black hole binaries in the low/hard state first harden as the flux decreases, then soften. This change in behaviour has been variously attributed to either the X-rays switching from being produced in the flow to being…
In earlier works, it was shown that the energy dependent soft time lags observed in kHz QPOs of neutron star low mass X-ray binaries (LMXBs) can be explained as being due to Comptonization lags provided a significant fraction ($\eta \sim…
We propose a jet model for the low/hard state of Galactic black-hole X-ray sources that can explain the energy spectra from radio to X-rays. The model assumes that i) there is a magnetic field along the axis of the jet; ii) the electron…
We use a simple one-dimensional parameterisation of timing properties to show that hard and hard-intermediate state transient black hole X-ray binaries with the same power-spectral shape have systematically harder X-ray power-law emission…
We discuss a new solution of the Kompaneets-equation for physical situations in which low frequency photons, forming relatively narrow spectral details, are Compton scattered in an isotropic, infinite medium with an intense ambient…
X-ray Compton spectroscopy is one of the few direct probes of the electron momentum distribution of bulk materials in ambient and operando environments. We report high-resolution inelastic X-ray scattering experiments with high momentum and…
We present a detailed study of the observable effects of photoionization and Comptonization of line and continuum radiation from a cold accretion disk with a thin, warm, photoionized transition layer in the framework of self-consistent…
To understand the origin of hard X-ray emissions from black hole X-ray binaries during their low/hard states, we calculate the X-ray spectra of black-hole accretion flow for the following three configurations of hot and cool media: (a) an…
I study the formation of Comptonization spectra in spherically symmetric, fast moving media in a flat spacetime. I analyze the mathematical character of the moments of the transfer equation in the system-frame and describe a numerical…
One of the most straightforward ways to explain the hard X-ray spectra observed in X-ray binaries is to assume that comptonization of soft photons from the accretion disk is occurring. The region where this process takes place, called the…
We present a detailed spectral analysis of the Black Hole Binary XTE J1752-223 in the hard state of its 2009 outburst. Regular monitoring of this source by RXTE provided high signal-to-noise spectra along the outburst rise and decay. During…
We present a Comptonization model for the observed properties of the energy-dependent soft/hard time lags and pulsed fraction (amplitude) associated with the pulsed emission of a neutron star (NS). We account for the soft lags by…
In this paper we test if the $\sim$ 0.3 - 15 keV XMM-Newton EPIC pn spectral continuum of IPs can be described by the thermal Comptonization compTT model. We used publicly observations of 12 IPs (AE Aqr, EX Hya, V1025 Cen, V2731 Oph, RX…
Accretion-powered X-ray pulsars are among the most luminous X-ray sources in the Galaxy. However, despite decades of theoretical and observational work since their discovery, no satisfactory model for the formation of the observed X-ray…