The XMM-Newton/2dF survey IV. The X-ray spectral properties of the hard sources

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

To appear in MNRAS

Scientific paper

10.1111/j.1365-2966.2004.07899.x

We present an analysis of the X-ray spectral properties of 61 hard X-ray selected (2-8 keV) sources from the bright ($f_{2-8 keV}>10^{-14}$ \funits) {\it XMM-Newton}/2dF survey. This comprises of 9 {\it XMM-Newton} pointings in the North Galactic Pole region ($\sim 1.6 \rm deg^2$) and overlaps with the SDSS, 2QZ and 2dFGRS surveys. Our sources contribute about 50 per cent of the 2-10 keV X-ray background down to the flux limit of $10^{-14}$ cgs. The hardness ratio distribution of the sample suggests a deficit of heavily absorbed sources. A spectral fit to the co-added total source spectrum yields a steep photon index, $\Gamma=1.83^{+0.04}_{-0.05}$. All but 8 sources have optical counterparts down to the SDSS photometric limit of $r\approx22.5$. Spectroscopic identifications exist for 34 sources. The vast majority are associated with Broad-Line (BL) AGN (24 sources) while only 7 present narrow or no emission lines. Five sources are probably associated with Galactic stars. Finally, for another 17 probable AGN we present photometric redshifts. The combined spectrum of the 24 spectroscopically identified BL AGN is steep ($\Gamma=2.02^{+0.04}_{-0.05}$), while that of the 7 AGN, which do not present broad lines is flatter with $\Gamma=1.64^{+0.11}_{-0.11}$. The spectrum of the 8 optically unidentified sources is flat with $\Gamma\approx 1.1$. Spectral fits to the individual BL AGN reveal large absorption (rest-frame column density $\rm>10^{22} cm^{-2}$) in only two cases. The individual spectra of the NL AGN present significant evidence for even a moderate absorption ($\rm 3\times 10^{21} cm^{-2}$) in only one case.

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

The XMM-Newton/2dF survey IV. The X-ray spectral properties of the hard sources 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 The XMM-Newton/2dF survey IV. The X-ray spectral properties of the hard sources, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The XMM-Newton/2dF survey IV. The X-ray spectral properties of the hard sources will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-144736

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