An X-ray selected sample of radio-loud quasars
Abstract
We construct the first X-ray selected sample of broad line radio-loud AGN from the EMSS survey. In order to test unifying schemes for radio-loud objects, their spectral and statistical properties (both flat and steep spectrum objects) are examined and compared with those of other samples of blazars. The X-ray selection allows us to explore properties of radio-loud quasars 10-100 weaker in the radio band than classical samples. The most convincing interpretation of our results is that there are no radio-loud quasars whose synchrotron emission peak reaches the EUV-soft X-ray band at these (radio) flux levels. Moreover, due to the comparatively weak non-thermal emission, a quasi-thermal component appears to contribute at optical-UV energies. The detection of sources at low radio fluxes also reveals a large population of steep spectrum quasars and the lack of the predicted turnover in the quasar (radio) counts. The evolution of X-ray selected radio-loud quasars does not significantly differ from that of radio-selected ones, and flat spectrum and steep spectrum sources appear to behave quite similarly.
Cite
@article{arxiv.astro-ph/0103394,
title = {An X-ray selected sample of radio-loud quasars},
author = {Anna Wolter and Annalisa Celotti},
journal= {arXiv preprint arXiv:astro-ph/0103394},
year = {2009}
}
Comments
11 pages, 10 figures, accepted for publication in Astronomy & Astrophysics