166 citations · 748 across the 18 of their papers we have counts for
10 papers · 1 filter
X-Ray Emission from the Quasar PKS 1127-145: Comptonized IR Photons on Parsec Scales
Michal Blazejowski, Aneta Siemiginowska, Marek Sikora +2
We model the broad-band spectral energy distribution of the innermost "core-jet" region of the redshift z=1.187 quasar PKS 1127-145. We propose a scenario where the high energy pho…
On the turbulent -disks and the intermittent activity in AGN
Agnieszka Janiuk, Bozena Czerny, Aneta Siemiginowska +1
We consider effects of the MHD turbulence on the viscosity during the evolution of the thermal-viscous ionization instability in the standard -accretion disks. We consider the p…
An X-ray jet discovered by Chandra in the z=4.3 radio-selected quasar GB 1508+5714
Aneta Siemiginowska, Randall K. Smith, Thomas L. Aldcroft +3
We report the Chandra discovery of an X-ray jet associated with the redshift 4.3 radio-loud quasar GB 1508+5714. The jet X-ray emission peaks ~2 arcsec to the South-West of the qua…
The origin of emission and absorption features in Ton S180 Chandra observations
A. Różańska, B. Czerny, A. Siemiginowska +2
We present new interpretation of Ton S180 spectrum obtained by {\it Chandra} Spectrometer (Low Energy Transmission Grating). Several narrow absorption lines and a few emission disk…
Constraints on AGN accretion disc viscosity derived from continuum variability
Rhaana L. C. Starling, Aneta Siemiginowska, Phil Uttley +1
We estimate a value of the viscosity parameter in AGN accretion discs for the PG quasar sample. We assume that optical variability on time-scales of months to years is caused by lo…
Chandra Observation of 3C 212: a New Look at the X-ray and UV Absorbers
T. L. Aldcroft, A. Siemiginowska, M. Elvis +3
The red quasar 3C 212 (z=1.049) is one of the most distant and most luminous AGN which has shown evidence of an X-ray warm absorber. In order to further investigate this unusual qu…