Zobrazeno 1 - 10
of 63
pro vyhledávání: '"Niedzwiecki, Andrzej"'
We study spectra produced by weakly accreting black hole (BH) systems using the semi-analytic advection dominated accretion flow (ADAF) model and the general-relativistic magentohydrodynamic (GRMHD) simulation. We find significant differences between
Externí odkaz:
http://arxiv.org/abs/2406.17200
Autor:
Zdziarski, Andrzej A., Chand, Swadesh, Banerjee, Srimanta, Szanecki, Michal, Janiuk, Agnieszka, Lubinski, Piotr, Niedzwiecki, Andrzej, Dewangan, Gulab, Misra, Ranjeev
We perform a detailed study of the black hole spin of Cyg X-1, using accurate broad-band X-ray data obtained in the soft spectral state by simultaneous NICER and NuSTAR observations, supplemented at high energies by INTEGRAL data. We use the relativi
Externí odkaz:
http://arxiv.org/abs/2402.12325
Autor:
Zdziarski, Andrzej A., Banerjee, Srimanta, Chand, Swadesh, Dewangan, Gulab, Misra, Ranjeev, Szanecki, Michal, Niedzwiecki, Andrzej
The black-hole spin parameter, $a_*$, was measured to be close to its maximum value of 1 in many accreting X-ray binaries. In particular, $a_*\gtrsim 0.9$ was found in a number of studies of LMC X-1. These measurements were claimed to take into accou
Externí odkaz:
http://arxiv.org/abs/2308.06167
We study the high energy emission of two active galactic nuclei (AGN), NGC 4258 and NGC 7213. We directly apply the general-relativistic (GR) hot flow model, kerrflow, to the archival BeppoSAX, NuSTAR and Suzaku observations of these objects. Most of
Externí odkaz:
http://arxiv.org/abs/2212.10973
Relativistic reflection observed in the hard states of accreting black holes often shows a weak amplitude relative to the main Comptonization component, which may result from either a disc truncation or a non-isotropy of the X-ray source, e.g. due to
Externí odkaz:
http://arxiv.org/abs/2212.01151
We have developed an improved model of X-ray emission from optically thin, two-temperature accretion flows, \texttt{kerrflow}, using an exact Monte Carlo treatment of global Comptonization as well as with a fully general relativistic description of b
Externí odkaz:
http://arxiv.org/abs/2205.10918
Autor:
Zdziarski, Andrzej A., Jourdain, Elisabeth, Lubinski, Piotr, Szanecki, Michal, Niedzwiecki, Andrzej, Veledina, Alexandra, Poutanen, Juri, Dzielak, Marta A., Roques, Jean-Pierre
We study X-ray and soft gamma-ray spectra from the hard state of the accreting black-hole binary MAXI J1820+070. We perform analysis of two joint spectra from NuSTAR and INTEGRAL, covering the range of 3--650 keV, and of an average joint spectrum ove
Externí odkaz:
http://arxiv.org/abs/2104.04316
Autor:
Zdziarski, Andrzej A., Dzielak, Marta A., De Marco, Barbara, Szanecki, Michal, Niedzwiecki, Andrzej
We study X-ray spectra from the outburst rise of the accreting black-hole binary MAXI J1820+070. We find that models having the disk inclinations within those of either the binary or the jet imply significant changes of the accretion disk inner radiu
Externí odkaz:
http://arxiv.org/abs/2101.04482
Autor:
Bambi, Cosimo, Brenneman, Laura W., Dauser, Thomas, Garcia, Javier A., Grinberg, Victoria, Ingram, Adam, Jiang, Jiachen, Liu, Honghui, Lohfink, Anne M., Marinucci, Andrea, Mastroserio, Guglielmo, Middei, Riccardo, Nampalliwar, Sourabh, Niedzwiecki, Andrzej, Steiner, James F., Tripathi, Ashutosh, Zdziarski, Andrzej A.
Publikováno v:
Space Sci. Rev. 217, 65 (2021)
Relativistic reflection features are commonly observed in the X-ray spectra of accreting black holes. In the presence of high quality data and with the correct astrophysical model, X-ray reflection spectroscopy can be quite a powerful tool to probe t
Externí odkaz:
http://arxiv.org/abs/2011.04792
We investigate the X-ray spectrum of the Seyfert galaxy NGC 4151 using the simultaneous Suzaku/NuSTAR observation and flux-resolved INTEGRAL spectra supplemented by Suzaku and XMM observations. Our best spectral solution indicates that the narrow Fe
Externí odkaz:
http://arxiv.org/abs/2010.08358