Related papers: Observational Constraints Upon Cool Disk Material …
We present angle-dependent, broad-band intensity spectra from accretion disks around black holes of 10 M$_\odot$. In our computations disks are assumed to be slim, which means that the radial advection is taken into account while computing…
We discuss the observational consequences of black hole spin in X-ray binaries within the framework of the standard thin accretion disk model. When compared to theoretical flux distribution from the surface of a thin disk surrounding a Kerr…
We compare the microlensing-based continuum emission region size measurements in a sample of 15 gravitationally lensed quasars with estimates of luminosity-based thin disk sizes to constrain the temperature profile of the quasar continuum…
Relativistic reflection features in the X-ray spectra of black hole binaries and AGNs are thought to be produced through illumination of a cold accretion disk by a hot corona. In this work, we assume that the corona has the shape of an…
We present simultaneous high-precision optical polarimetric and near-infrared (NIR) to ultraviolet (UV) photometric observations of low-mass black hole X-ray binary A0620-00 in the quiescent state. Subtracting interstellar polarization,…
In this letter, we comment on the robustness of putative cool (kT ~ 0.2 keV) accretion disc components in the X-ray spectra of the most luminous (L ~ 10^40 erg/s) ultra-luminous X-ray sources (ULXs) in nearby normal galaxies. When compared…
This study investigates the accretion process and observational signatures of thin accretion disks around a Schwarzschild black hole (BH) embedded in a Dehnen-type dark matter (DM) halo. We examine the influence of the density {\rho}_{s}…
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-free and free-free opacities of all abundant…
The absence of thermal instability in the high/soft state of black hole X-ray binaries, in disagreement with the standard thin disk theory, is a long-standing riddle for theoretical astronomers. We have tried to resolve this question by…
The standard thin accretion disc model predicts that discs around stellar mass black holes become radiation pressure dominated and thermally unstable once their luminosity exceeds L>0.02 L_Edd. Observationally, discs in the high/soft state…
Recent X-ray timing and spectral observations of black hole binaries in outburst have redefined methods for investigating the properties of Galactic black holes and the physics of accretion flows. High-frequency X-ray QPOs in 5 systems…
The advent of gravitational-wave astronomy is now allowing for the study of compact binary merger demographics throughout the Universe. This information can be leveraged as tools for understanding massive stars, their environments, and…
We test the truncated disc models using multiwavelength (optical/UV/X-ray) data from the 2005 hard state outburst of the black hole SWIFT J1753.5-0127. This system is both fairly bright and has fairly low interstellar absorption, so gives…
We demonstrate that gas disks around binary systems might deliver gas to the binary components only when the circumbinary disk is relatively warm. We present new grid-based hydrodynamics simulations, performed with the binary on the grid…
We describe the first complete polarimetric dataset of the entire outburst of a low-mass black hole X-ray binary system and discuss the constraints for geometry and radiative mechanisms it imposes. During the decaying hard state, when the…
We investigate the behaviour of the accretion discs in the outbursts of the low-mass black-hole X-ray binaries (BHXRB), an overview of which we have presented previously. Almost all of the systems in which there are sufficient observations…
Hard X-ray spectra of black hole binaries in the low/hard state are well modeled by thermal Comptonization of soft seed photons by a corona-type region with $kT$\thinspace$\sim 50${\thinspace}keV and optical depth around 1. Previous…
The masses of compact objects in X-ray binaries are best constrained through dynamical measurements, relying on radial velocity curves of the companion star. In anticipation of upcoming high X-ray spectral resolution telescopes, we explore…
Accreting binaries containing a black hole are stellar systems composed of a normal star and a black hole. Because of the strong gravitational pull of the black hole, matter is removed from the companion star and falls into the compact ob…
The properties of precessing, coalescing binary black holes are presently inferred through comparison with two approximate models of compact binary coalescence. In this work we show these two models often disagree substantially when…