Serendipitous discovery of a redshift 4.4 QSO

view Abstract Citations (42) References (18) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Serendipitous Discovery of a Redshift 4.4 QSO McCarthy, Patrick J. ; Dickinson, Mark ; Filippenko, Alexei V. ; Spinrad, Hyron ; van Breugel, Wil J. M. Abstract We report the serendipitous discovery of an extremely high-redshift quasar (QSO), designated Q2203+29. It was found during long-slit observations of the radio galaxy 3C 441. The QSO spectrum contains strong emission lines of Lyα, N V λ1240, and C IV λ1549, as well as weaker Lyβ, O VI λ1034, Si II λ1262, and Si IV/O IV] λ1400. There is prominent break in the continuum level blueward of Lyα. The derived reshift is 4.406+/-0.005, one of the highest known. Deep broad-band imaging reveals no resolved structure, as expected for a very distant QSO. The r magnitude of the QSO is 20.8. Lyα interference filter imaging shows no emission-line companions or extended emission down to surface brightness levels of 22.5 mag arcsec^-2^. The broad-band images show a faint disk galaxy with z = 0.2, loacted 7" away from the QSO. Our spectra do not exhibit any absorption lines produced by this foreground galaxy. The VLA observations at λ = 20 cm fail to reveal any detectable emission from the QSO to a 3σ upper limit of 1.8 mJy beam^-1^. this is the first serendipitously discovered QSO of any redshift in nearly 5 yr of long-slit CCD spectroscopy of radio sources at Kitt Peak and Lick Observatories. Publication: The Astrophysical Journal Pub Date: May 1988 DOI: 10.1086/185154 Bibcode: 1988ApJ...328L..29M Keywords: Emission Spectra; Lyman Alpha Radiation; Quasars; Red Shift; Line Spectra; Radio Galaxies; Astrophysics; QUASARS; RADIO SOURCES: GALAXIES full text sources ADS | data products NED (3)