Six More Quasars at Redshift 6 Discovered by the Canada-france High-z Quasar Survey
نویسنده
چکیده
We present imaging and spectroscopic observations for six quasars at z ≥ 5.9 discovered by the CanadaFrance High-z Quasar Survey (CFHQS). The CFHQS contains sub-surveys with a range of flux and area combinations to sample a wide range of quasar luminosities at z ∼ 6. The new quasars have luminosities 10 to 75 times lower than the most luminous SDSS quasars at this redshift. The least luminous quasar, CFHQS J02160455 at z = 6.01, has absolute magnitude M1450 = −22.21, well below the likely break in the luminosity function. This quasar is not detected in a deep XMM-Newton survey showing that optical selection is still a very efficient tool for finding high redshift quasars. Subject headings: cosmology: observations — quasars: general — quasars: emission lines
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