相关论文: Radiation Transfer of Emission Lines in Curved Spa…

We use a relativistic ray-tracing code to calculate the light curves observed from a global general relativistic magneto-hydrodynamic simulation of an accretion flow onto a Schwarzschild black hole. We apply three basic emission models to…

We model the light-curves from radiation-driven clouds near an accreting black hole. Taking into account the multiple images due to strong gravitational lensing, we find that sharp spikes can significantly enhance the observed flux.…

General covariant expressions for measurable angles, distances, velocities, and accelerations are provided in terms of fundamental parameters that can be applied in any setup. The relativistic aberration of light relationship is presented…

Currently available information on fast variability of the X-ray emission from accreting collapsed objects constitutes a complex phenomenology which is difficult to interpret. We review the current observational standpoint for black-hole…

We consider photon emission from a supercritical accretion disk in which photons in the inner regions are trapped and advected in towards the center. Such disks are believed to be present in failed supernovae and gamma-ray bursts, and…

Due to the impressive amount of new data provided by the RXTE satellite in the past decade, our knowledge of the phenomenology of accretion onto black holes has increased considerably. In particular, it has been possible to schematize the…

Relativistic radiative transfer problems require the calculation of photon trajectories in curved spacetime. We present a novel technique for rapid and accurate calculation of null geodesics in the Kerr metric. The equations of motion from…

Alternative versions of the Klein-Gordon and Dirac equations in a curved spacetime are got by applying directly the classical-quantum correspondence.

Generalizing to relativistic exponential scaling and using the theory of noise from quantum fluctuations, it has been shown that one vacuum (Rindler, Hartle-Hawking, or Gibbons-Hawking for the cases of the uniformly accelerated detector,…

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 between changes in the direct coronal…

We present the results of our studies on accretion disks in the proximity of astrophysical black holes. These disks can be of varying degrees of opacity, geometrical shapes, sizes, and volumes. The central compact object is a Schwarzschild…

We study the neutrino scattering off a rotating black hole with a realistic accretion disk permeated by an intrinsic magnetic field. Neutrino trajectories in curved spacetime as well as the particle spin evolution in dense matter of an…

We present the first X-ray reflection model for testing the assumption that the metric of astrophysical black holes is described by the Kerr solution. We employ the formalism of the transfer function proposed by Cunningham. The calculations…

We consider the propagation of a generic scalar field around a rotating and charged black hole. Using the partial wave method, we find, numerically, the total and partial absorption cross sections for different incidence angles. We…

The non-spherically symmetric transport equations and exact thermal evolution model are used to calculate the transient thermal response to pulsars. The three possible ways of energy release originated from glitches, namely the `shell',…

Raytracing computations for light emitted from the surface of a rapidly rotating neutron star are carried out in order to construct light curves for accreting millisecond pulsars. These calculations are for realistic models of rapidly…

The thesis studies the X-ray emission from the Galactic compact objects (accreting neutron stars and black holes), using mainly the RXTE data. In particular following results have been included: spectral evolution of X-ray transients GRS…

We study electromagnetic perturbations around a Kerr black hole surrounded by a thin disk on the equatorial plane. Our main purpose is to reveal the black hole superradiance of electromagnetic waves emitted from the disk surface. The…

It is commonly assumed that in black hole accretion disks the angular momenta of the disk and the black hole are aligned. However, for a significant fraction of stellar mass black holes and supermassive black holes, the momenta may not be…

We study null rays propagation in a spacetime of static Schwarzschild--Tangherlini black holes in arbitrary number of dimensions. We focus on the bending angle and the retarded time delay for rays emitted in the vicinity of a black hole and…