TY - JOUR
T1 - Discovery of a redshift 6.13 quasar in the UKIRT infrared deep sky survey
AU - Mortlock, D.J.
AU - Patel, M.
AU - Warren, S.J.
AU - Venemans, B.P.
AU - McMahon, R.G.
AU - Hewett, P.C.
AU - Simpson, C.
AU - Sharp, R.G.
AU - Burningham, B.
AU - Dye, S.
AU - Ellis, S.
AU - Gonzales-Solares, E.
AU - Huelamo, N.
N1 - Original article can be found at: http://www.aanda.org/ Copyright The European Southern Observatory (ESO) DOI: 10.1051/0004-6361/200811161
PY - 2009
Y1 - 2009
N2 - Optical and near-infrared (NIR) spectra are presented for ULAS J131911.29+095051.4 (hereafter ULAS J1319+0950), a new redshift z = 6.127 0.004 quasar discovered in the Third Data Release (DR3) of the UKIRT Infrared Deep Sky Survey (UKIDSS). The source has = 19.10 0.03, corresponding to = -27.12, which is comparable to the absolute magnitudes of the z 6 quasars discovered in the Sloan Digital Sky Survey (SDSS). ULAS J1319+0950 was, in fact, registered by SDSS as a faint source with = 20.13 0.12, just below the signal-to-noise ratio limit of the SDSS high-redshift quasar survey. The faint z-band magnitude is a consequence of the weak Ly /N V emission line, which has a rest-frame equivalent width of ~20Å and provides only a small boost to the z-band flux. Nevertheless, there is no evidence of a significant new population of high-redshift quasars with weak emission lines from this UKIDSS-based search. The Ly optical depth to ULAS J1319+0950 is consistent with that measured towards similarly distant SDSS quasars, implying that results from optical- and NIR-selected quasars may be combined in studies of cosmological reionization. Also presented is a new NIR-spectrum of the previously discovered UKIDSS quasar ULAS J020332.38+001229.2, which reveals the object to be a broad absorption line quasar. The new spectrum shows that the emission line initially identified as Ly is actually N V, leading to a revised redshift of z = 5.72, rather than z = 5.86 as previously estimated
AB - Optical and near-infrared (NIR) spectra are presented for ULAS J131911.29+095051.4 (hereafter ULAS J1319+0950), a new redshift z = 6.127 0.004 quasar discovered in the Third Data Release (DR3) of the UKIRT Infrared Deep Sky Survey (UKIDSS). The source has = 19.10 0.03, corresponding to = -27.12, which is comparable to the absolute magnitudes of the z 6 quasars discovered in the Sloan Digital Sky Survey (SDSS). ULAS J1319+0950 was, in fact, registered by SDSS as a faint source with = 20.13 0.12, just below the signal-to-noise ratio limit of the SDSS high-redshift quasar survey. The faint z-band magnitude is a consequence of the weak Ly /N V emission line, which has a rest-frame equivalent width of ~20Å and provides only a small boost to the z-band flux. Nevertheless, there is no evidence of a significant new population of high-redshift quasars with weak emission lines from this UKIDSS-based search. The Ly optical depth to ULAS J1319+0950 is consistent with that measured towards similarly distant SDSS quasars, implying that results from optical- and NIR-selected quasars may be combined in studies of cosmological reionization. Also presented is a new NIR-spectrum of the previously discovered UKIDSS quasar ULAS J020332.38+001229.2, which reveals the object to be a broad absorption line quasar. The new spectrum shows that the emission line initially identified as Ly is actually N V, leading to a revised redshift of z = 5.72, rather than z = 5.86 as previously estimated
U2 - 10.1051/0004-6361/200811161
DO - 10.1051/0004-6361/200811161
M3 - Article
SN - 0004-6361
VL - 505
SP - 97
EP - 104
JO - Astronomy and Astrophysics
JF - Astronomy and Astrophysics
IS - 1
ER -