272 citations · 1.6k across the 43 of their papers we have counts for
4 papers · 1 filter
Energy spectra of X-ray quasi-periodic oscillations in accreting black hole binaries
P. T. Zycki, M. A. Sobolewska, A. Niedzwiecki
We investigate the energy dependencies of X-ray quasi-periodic oscillations in black hole X-ray binaries. We analyze RXTE data on both the low- and high-frequency QPO. We construct…
Evolution of the X-ray Emission of Radio-Quiet Quasars
Brandon C. Kelly, Jill Bechtold, Aneta Siemiginowska +2
We report new Chandra observations of seven optically faint, z \sim 4 radio-quiet quasars. We have combined these new observations with previous Chandra observations of radio-quiet…
The iron K feature in Narrow Line Seyfert 1's: evidence for a P Cygni profile?
C. Done, M. A. Sobolewska, Marek Gierlinski +1
Narrow Line Seyfert 1 galaxies are generally accreting at high fractions of the Eddington limit. They can show complex X-ray spectra, with a strong `soft excess' below 2 keV and a…
Spectral and Fourier analyses of X-ray QPO in accreting black holes
M. A. Sobolewska, P. T. Zycki
We study energy dependencies of quasi-periodic oscillations from a number of black hole X-ray binaries. The selected sources were observed by RXTE at time periods close to state tr…