A Classic Type 2 QSO

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

24 LaTeX pages including 6 postscript figures. Revised version, accepted by ApJ

Scientific paper

10.1086/339855

In the Chandra Deep Field South 1Msec exposure we have found, at redshift 3.700 +- 0.005, the most distant Type 2 AGN ever detected. It is the source with the hardest X-ray spectrum with redshift z>3. The optical spectrum has no detected continuum emission to a 3sigma detection limit of ~3 10^{-19} ergs/s/cm^2/AA and shows narrow lines of Ly_alpha, CIV, NV, HeII, OVI, [OIII], and CIII]. Their FWHM line widths have a range of ~700-2300 km/s with an average of approximately ~1500 km/s. The emitting gas is metal rich (Z ~2.5-3 Z_solar). In the X-ray spectrum of 130 counts in the 0.5-7 keV band there is evidence for intrinsic absorption with N_H > 10^{24} cm^{-2}. An iron K_alpha line with rest frame energy and equivalent width of ~6.4 keV and ~1 keV, respectively, in agreement with the obscuration scenario, is detected at a 2sigma level. If confirmed by our forthcoming XMM observations this would be the highest redshift detection of FeK_alpha. Depending on the assumed cosmology and the X-ray transfer model, the 2-10 keV rest frame luminosity corrected for absorption is ~10^{45 +- 0.5} ergs/s, which makes our source a classic example of the long sought Type 2 QSOs. From standard population synthesis models, these sources are expected to account for a relevant fraction of the black-hole-powered QSO distribution at high redshift.

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

A Classic Type 2 QSO 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 A Classic Type 2 QSO, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A Classic Type 2 QSO will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-175789

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