相关论文: Higher Order Variability Properties of Accreting B…

We describe how the coherence function, a Fourier frequency-dependent measure of the linear correlation between time series measured simultaneously in two energy channels, can be used in conjunction with energy spectra, power spectra, and…

We present first results from the spectral and temporal analysis of an RXTE monitoring campaign of the black hole candidate Cygnus X-1 in 1999. The timing properties of this hard state black hole show considerable variability, even though…

Here we present timing analysis of a set of eight Rossi X-ray Timing Explorer (RXTE) observations of the black hole candidate GX 339-4 that were taken during its hard/low state. On long time scales, the RXTE All Sky Monitor data reveal…

The first seven years of RXTE monitoring of Seyfert 1 active galactic nuclei have been systematically analyzed to yield five homogeneous samples of 2-12 keV light curves, probing hard X-ray variability on successively longer durations from…

We present results from a 20 ksec RXTE observation of the black hole candidate Cyg X-1. We apply self-consistent accretion disk corona models to these hard state data and show that Comptonization in a spherical corona irradiated by soft…

We study the rapid variability in Cyg X-1 observed with the Rossi Timing Explorer (RXTE) on Jan 17 and 20 of 1997. The power spectra below 200 Hz can be characterized by two ``shot noise'' components and a peaked-noise centered at 0.2 Hz.…

We discuss the results of long-term hard x-ray monitoring of Galactic black-hole candidates 1E 1740.7-2942, GRS 1758-258, Cyg X-1, GX 339-4, and Cyg X-3 with the Rossi X-Ray Timing Explorer (RXTE). The objects divide into two classes. In…

The black hole candidates exhibit fast variability of their X-ray emission on a wide range of timescales. The short, coherent variations, with frequencies above 1 Hz, are referred to as quasi-periodic oscillations, and are generally…

The short-term X-ray variability of Cyg X-1 can be interpreted as random occurrence of mini-flares known as the shots, whose physical nature is still unclear. We propose a new algorithm for shot identification in the X-ray light curve,…

A rapid timing analysis of VLT/ULTRACAM and RXTE observations of the black hole binary GX 339-4 in its 2007 low/hard state is presented. The optical light curves in the r', g' and u' filters show slow (~20 s) quasi-periodic variability.…

There have been a number of recent spectral models that have been successful in reproducing the observed X-ray spectra of galactic black hole candidates (GBHC). However, there still exists controversy over such issues as: what are the…

I discuss some practical aspects of the analysis of millisecond time variability X-ray data obtained from accreting neutron stars and black holes. First I give an account of the statistical methods that are at present commonly applied in…

Flux variability is a remarkable property of black hole (BH) accreting systems, and a powerful tool to investigate the multi-scale structure of the accretion flow. The X-ray band is where some of the most rapid variations occur, pointing to…

In order to investigate the dependence of quasar optical-UV variability on fundamental physical parameters like black hole mass, we have matched quasars from the QUEST1 variability survey with broad-lined objects from the SDSS. Black hole…

We present model light curves, Power Spectral Densities (PSD) and time lags of accreting Black Hole Candidates (BHC) based on a recent model of these sources. According to our model the observed variability is due, to a large extent, to the…

Black hole X-ray binaries display significant stochastic variability on short time-scales (0.01-100 seconds), with a complex pattern of lags in correlated variability seen in different energy bands. This behaviour is generally interpreted…

The spectra of black hole binaries in the low/hard state are complex, with evidence for multiple different Comptonisation regions contributing to the hard X-rays in addition to a cool disc component. We show this explicitly for some of the…

We present the most extensive analysis of Fourier-based X-ray timing properties of the black hole binary Cygnus X-1 to date, based on 12 years of bi-weekly monitoring with RXTE from 1999 to 2011. Our aim is a comprehensive study of timing…

We present model light curves for accreting Black Hole Candidates (BHC) based on a recently proposed model for their spectro-temporal properties. According to this model, the observed light curves and aperiodic variability of BHC are due to…

The entire dataset of the GRANAT/SIGMA observations of Cyg X-1 and 1E1740.7-2942 in 1990-1994 was analyzed in order to search for correlations between primary observational characteristics of the hard X-ray (40-200 keV) emission - hard…