XMM-Newton observations of 3C 273
Abstract
A series of nine XMM-Newton observations of the radio-loud quasar 3C 273 are presented, concentrating mainly on the soft excess. Although most of the individual observations do not show evidence for iron emission, co-adding them reveals a weak, broad line (EW ~ 56 eV). The soft excess component is found to vary, confirming previous work, and can be well fitted with multiple blackbody components, with temperatures ranging between ~40 and ~330 eV, together with a power-law. Alternatively, a Comptonisation model also provides a good fit, with a mean electron temperature of ~350 eV, although this value is higher when the soft excess is more luminous over the 0.5-10 keV energy band. In the RGS spectrum of 3C 273, a strong detection of the OVII He-alpha absorption line at zero redshift is made; this may originate in warm gas in the local intergalactic medium, consistent with the findings of both Fang et al. (2003) and Rasmussen et al. (2003).
Cite
@article{arxiv.astro-ph/0312148,
title = {XMM-Newton observations of 3C 273},
author = {K. L. Page and M. J. L. Turner and C. Done and P. T. O'Brien and J. N. Reeves and S. Sembay and M. Stuhlinger},
journal= {arXiv preprint arXiv:astro-ph/0312148},
year = {2008}
}
Comments
12 pages, 19 figures, accepted for publication in MNRAS