271 citations · 4.6k across the 192 of their papers we have counts for
9 papers · 2 filters
Wavelet analysis of millisecond variability of Cygnus X-1 during its failed state transition
Pawel Lachowicz, Bozena Czerny
Application of multi-resolution analysis adopting wavelets in order to investigate millisecond aperiodic X-ray variability of Cyg X-1 is presented. This relatively new approach in…
X-ray Variability of AGN and the Flare Model
R. W. Goosmann, B. Czerny, A. -M. Dumont +2
Short-term variability of X-ray continuum spectra has been reported for several Active Galactic Nuclei. Significant X-ray flux variations are observed within time scales down to 10…
Time delays between the soft and hard X-ray bands in GRS 1915+105
Agnieszka Janiuk, Bozena Czerny
The hard X-ray lightcurves exhibit delays of s with respect to the soft X-ray lightcurves when the microquasar GRS 1915+105 is in the state of frequent, regular outbursts…
The role of an accretion disk in AGN variability
B. Czerny
Optically thick accretion disks are considered to be important ingredients of luminous AGN. The claim of their existence is well supported by observations and recent years brought…
Irradiation of accretion discs in active galactic nuclei due to warm absorber
Z. Loska, B. Czerny, R. Szczerba
The presence of the warm absorber of considerable optical depth is seen in many AGN. We show that this medium may affect significantly the optical/UV spectrum of an AGN by backscat…
Low angular momentum accretion-outflow model of flares from Sgr A
Tapas K. Das, Bozena Czerny
We employ a low angular momentum accretion-outflow scenario to model the flares emanating out from the central region of Sgr A. The primary donor for matter accreting onto the…
Evolution of a neutrino-cooled disc in Gamma-Ray Bursts
Agnieszka Janiuk, Rosalba Perna, Tiziana Di Matteo +1
Rapid, hyper-Eddington accretion is likely to power the central engines of gamma-ray bursts (GRBs). In the extreme conditions of densities and temperatures the accreting torus is c…
The structure and radiation spectra of illuminated accretion disks in AGN. II. Flare/spot model of X-ray variability
B. Czerny, A. Rozanska, M. Dovciak +2
We discuss a model of X-ray variability of active galactic nuclei (AGN). We consider multiple spots which originate on the surface of an accretion disk following intense irradiatio…
Extinction due to amorphous carbon grains in red quasars from the SDSS
B. Czerny, J. Li, Z. Loska +1
We construct a quasar extinction curve based on the blue and red composite quasar spectra of Richards et al. (2003) prepared from the SDSS survey. This extinction curve does not sh…