DES J0454-4448: discovery of the first luminous z %26gt;= 6 quasar from the Dark Energy Survey

作者：Reed S L; McMahon R G; Banerji M; Becker G D; Gonzalez Solares E; Martini P; Ostrovski F; Rauch M; Abbott T; Abdalla F B; Allam S; Benoit Levy A; Bertin E; Buckley Geer E; Burke D; Rosell A Carnero; da Costa L N; D' Andrea C; DePoy D L; Desai S; Diehl H T; Doel P; Cunha C E; Estrada J; Evrard A E; Neto A Fausti; Finley D A; Fosalba P; Frieman J; Gruen D; Honscheid K; James D; Kent S; Kuehn K; Kuropatkin N

来源：Monthly Notices of the Royal Astronomical Society, 2015, 454(4): 3952-3961.

DOI：10.1093/mnras/stv2031

• galaxies: active
• galaxies: formation
• galaxies: high-redshift
• quasars: individual: DES J0454-4448
• dark ages, reionization, first stars

We present the first results of a survey for high-redshift, z >= 6, quasars using izY multicolour photometric observations from the Dark Energy Survey (DES). Here we report the discovery and spectroscopic confirmation of the Z(AB), Y-AB = 20.2, 20.2 (M-1450 = -26.5) quasar DES J0454-4448 with a redshift of z = 6.09 +/- 0.02 based on the onset of the Ly alpha forest and an H I near zone size of 4.1(-1.2)(+1.1) proper Mpc. The quasar was selected as an i-band drop out with i-z = 2.46 and z(AB) < 21.5 from an area of similar to 300 deg(2). It is the brightest of our 43 candidates and was identified for spectroscopic follow-up solely based on the DES i-z and z-Y colours. The quasar is detected by WISE and has W1(AB) = 19.68. The discovery of one spectroscopically confirmed quasar with 5.7 < z < 6.5 and z(AB) <= 20.2 is consistent with recent determinations of the luminosity function at z similar to 6. DES when completed will have imaged -5000 deg2 to Y-AB = 23.0 (5 sigma point source) and we expect to discover 50-100 new quasars with z > 6 including 3-10 with z > 7 dramatically increasing the numbers of quasars currently known that are suitable for detailed studies.

• 出版日期2015-12-21