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Title: DES J0454–4448: Discovery of the first luminous z ≥ 6 quasar from the Dark Energy Survey

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 α forest and an H i near zone size of 4.1 +1.1 –1.2 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 ~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 ~ 6. DES when completed will have imaged ~5000 deg 2 to Y AB = 23.0 (5σ point source) and we expect to discover 50–100 new quasars with z > 6 including 3–10more » with z > 7 dramatically increasing the numbers of quasars currently known that are suitable for detailed studies.« less
  1. Univ. of Cambridge, Cambridge (United Kingdom). et al.
Publication Date:
Report Number(s):
FERMILAB-PUB-15-140-AE; BNL-111932-2016-JA
Journal ID: ISSN 0035-8711; arXiv eprint number arXiv:1504.03264
Grant/Contract Number:
AC02-07CH11359; SC00112704
Accepted Manuscript
Journal Name:
Monthly Notices of the Royal Astronomical Society
Additional Journal Information:
Journal Volume: 454; Journal Issue: 4; Journal ID: ISSN 0035-8711
Royal Astronomical Society
Research Org:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Contributing Orgs:
Country of Publication:
United States
79 ASTRONOMY AND ASTROPHYSICS; dark ages; reionization; first stars; galaxies: active; galaxies: formation; galaxies: high redshift; quasars: individual: DES J0454-4448; galaxies: high-redshift; reionizaion
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1245385