Abstract
We present X-ray and optical observations of CXOMP J213945.0234655, a high-redshift (z p 4.93) quasar discovered through the Chandra Multiwavelength Project (ChaMP). This object is the most distant X-ray–selected quasar published, with a rest-frame X-ray luminosity of L X p 5.9 # 10 44 ergs s1 (measured in the 0.3–2.5 keV band and corrected for Galactic absorption). CXOMP J213945.0234655 is a g dropout object (126.2), with r p 22.87 and i p 21.36. The rest-frame X-ray–to–optical flux ratio is similar to quasars at lower redshifts and slightly X-ray bright relative to z 1 4 optically selected quasars observed with Chandra. The ChaMP is beginning to acquire significant numbers of high-redshift quasars to investigate the X-ray luminosity function out to z ∼ 5.
Original language | English (US) |
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Pages (from-to) | L1-L4 |
Journal | Astrophysical Journal Letters |
Volume | 569 |
Issue number | 1 |
DOIs | |
State | Published - Mar 20 2002 |
Keywords
- Galaxies: active
- Galaxies: nuclei
- Quasars: general
- Quasars: individual (CXOMP J213945.0234655)
- X-rays: general
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science