X-ray emission from radio-quiet quasars in the SDSS Early Data Release. The alpha_ox dependence upon UV luminosity

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

14 pages, 8 figures included, 3 tables, LaTeX emulateapj5.sty, accepted for publication by the Astronomical Journal (Feb. 2003

Scientific paper

10.1086/345973

We investigate the X-ray properties of the color-selected radio-quiet quasars (RQQs) in the Sloan Digital Sky Survey (SDSS) Early Data Release using ROSAT, Chandra, and XMM-Newton data. In the 0.16-6.28 redshift range, 136 RQQs have X-ray detections (69 from the ROSAT All-Sky Survey, RASS), while for 70 RQQs X-ray upper limits are obtained. The well-defined selection method utilized by the SDSS, coupled with the tight radio constraints from the FIRST/NVSS surveys, allow us to define a representative sample of optically selected RQQs whose broad-band spectral energy distributions (characterized by means of the optical-to-X-ray spectral index, alpha_ox) can be studied as a function of rest-frame ultraviolet (UV) luminosity and redshift. A partial correlation analysis applied to the SDSS sample (including the upper limits, but excluding the biased subsample of RASS detections) shows that alpha_ox is a function of rest-frame UV luminosity (i.e., alpha_ox steepens at high UV luminosities); this correlation is significant at the 3.7 sigma level. We do not detect a highly significant redshift dependence of alpha_ox. We also find a significant (7.8 sigma level) correlation between UV and X-ray luminosity. This correlation, parameterized by Lx \propto Luv^{0.75+/-0.06}, extends previous results to the highest redshifts.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

X-ray emission from radio-quiet quasars in the SDSS Early Data Release. The alpha_ox dependence upon UV luminosity does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with X-ray emission from radio-quiet quasars in the SDSS Early Data Release. The alpha_ox dependence upon UV luminosity, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and X-ray emission from radio-quiet quasars in the SDSS Early Data Release. The alpha_ox dependence upon UV luminosity will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-406695

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.