Skip to main content

Research Repository

Advanced Search

Broadband short term variability of the quasar PDS 456

Broadband short term variability of the quasar PDS 456 Thumbnail


Abstract

We present a detailed analysis of a recent $500$ ks net exposure \textit{Suzaku} observation, carried out in 2013, of the nearby ($z=0.184$) luminous (L$_{\rm bol}\sim10^{47}$ erg s$^{-1}$) quasar PDS 456 in which the X-ray flux was unusually low. The short term X-ray spectral variability has been interpreted in terms of variable absorption and/or intrinsic continuum changes. In the former scenario, the spectral variability is due to variable covering factors of two regions of partially covering absorbers. We find that these absorbers are characterised by an outflow velocity comparable to that of the highly ionised wind, i.e. $\sim0.25$ c, at the $99.9\%$ $(3.26\sigma)$ confidence level. This suggests that the partially absorbing clouds may be the denser clumpy part of the inhomogeneous wind. Following an obscuration event we obtained a direct estimate of the size of the X-ray emitting region, to be not larger than $20~R_{\rm g}$ in PDS 456.

Acceptance Date Jan 15, 2016
Publication Date Apr 25, 2016
Publicly Available Date Mar 28, 2024
Journal Astronomische Nachrichten
Print ISSN 0004-6337
Publisher Wiley
Pages 495-499
DOI https://doi.org/10.1002/asna.201612336
Keywords Black hole physics, galaxies, active, nuclei, quasars, individual, PDS 456, x-rays
Publisher URL http://dx.doi.org/10.1002/asna.201612336

Files




Downloadable Citations