The Dark Energy Spectroscopic Instrument (DESI) is carrying out a five-year survey that aims to measure the redshifts of tens of millions of galaxies and quasars, including 8 million luminous red galaxies (LRGs) in the redshift range 0.4 <
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Quasar UV Luminosity Function at 3.5 < z < 5.0 from SDSS Deep Imaging Data
Abstract We present a well-designed sample of more than 1000 type 1 quasars at 3.5 < z < 5 and derive UV quasar luminosity functions (QLFs) in this redshift range. These quasars were selected using the Sloan Digital Sky Survey (SDSS) imaging data in the Stripe 82 and overlap regions with repeat imaging observations that are about 1 mag fainter than the SDSS single-epoch data. The follow-up spectroscopic observations were conducted by the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS) as one of the BOSS ancillary programs. Reaching i ∼ 21.5 mag, our sample bridges previous samples from brighter and deeper surveys. We use a 1/ V a method to derive binned QLFs at 3.6 < z < 4.0, 4.0 < z < 4.5, and 4.5 < z < 4.9 and then use a double power-law model to parameterize the QLFs. We also combine our data with literature QLFs to better constrain the QLFs across a much wider luminosity baseline. The faint- and bright-end slopes of the QLFs in this redshift range are around −1.7 and −3.7, respectively, with uncertainties from 0.2 to 0.3 to >0.5. The evolution of the QLFs from z ∼ 5 to 3.5 can be described by more »
- Award ID(s):
- 1908284
- Publication Date:
- NSF-PAR ID:
- 10381317
- Journal Name:
- The Astrophysical Journal
- Volume:
- 928
- Issue:
- 2
- Page Range or eLocation-ID:
- 172
- ISSN:
- 0004-637X
- Sponsoring Org:
- National Science Foundation
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