The Infrared Medium-deep Survey. III. Survey of Luminous Quasars at 4.7 $\le$ z $\le$ 5.4

Abstract

We present our first results of the survey for high redshift quasars at $5\lesssim \mathrm{z}\lesssim 5.7$. The search for quasars in this redshift range has been known to be challenging due to limitations of filter sets used in previous studies. We conducted a quasar survey for two specific redshift ranges, 4.60 $\le$ z $\le$ 5.40 and 5.50 $\le$ z $\le$ 6.05, using multi-wavelength data that include observations using custom-designed filters, $is$ and $iz$. Using these filters and a new selection technique, we were able to reduce the fraction of interlopers. Through optical spectroscopy, we confirmed seven quasars at 4.7 $\le$ z $\le$ 5.4 with $-27.4<M_{1450}<-26.4$ which were discovered independently by another group recently. We estimated black hole masses and Eddington ratios of four of these quasars from optical and near-infrared spectra, and found that these quasars are undergoing nearly Eddington-limited accretion which is consistent with the rapid growth of supermassive black holes in luminous quasars at z $\sim$ 5.

16 pages, 12 figures, and 9 tables. Accepted for publication in ApJS

References in corpus (24)

• The UKIRT Infrared Deep Sky Survey (UKIDSS)
• A Catalog of Quasar Properties from SDSS DR7
• A luminous quasar at a redshift of z = 7.085
• An ultra-luminous quasar with a twelve-billion-solar-mass black hole at redshift 6.30
• Biases in Virial Black Hole Masses: An SDSS Perspective
• Four quasars above redshift 6 discovered by the Canada-France High-z Quasar Survey
• Gemini Near-infrared Spectroscopy of Luminous z~6 Quasars: Chemical Abundances, Black Hole Masses, and MgII Absorption
• Fe II Emission in 14 Low-Redshift Quasars: I - Observations
• Black hole masses and enrichment of z ~ 6 SDSS quasars
• Spitzer/IRAC Photometry of M, L, and T Dwarfs
• A Survey of z~6 Quasars in the SDSS Deep Stripe: I. a Flux-Limited Sample at z_{AB}<21
• The identification of z-dropouts in Pan-STARRS1: three quasars at 6.5<z<6.7
• Discovery of eight z ~ 6 quasars from Pan-STARRS1
• Six more quasars at redshift 6 discovered by the Canada-France High-z Quasar Survey
• The UV Continuum of Quasars: Models and SDSS Spectral Slopes
• Dust-free quasars in the early Universe
• The Subaru high-z quasar survey: discovery of faint z~6 quasars
• A survey of luminous high-redshift quasars with SDSS and WISE II. the bright end of the quasar luminosity function at z ~ 5
• Rest-frame Optical Spectra and Black Hole Masses of 3<z<6 Quasars
• The Discovery of Three New z>5 Quasars in the AGN and Galaxy Evolution Survey
• Discovery of Eight z ~ 6 Quasars in the Sloan Digital Sky Survey Overlap Regions
• Ultra-cool dwarfs: new discoveries, proper motions, and improved spectral typing from SDSS and 2MASS photometric colors
• A New Approach to Constrain Black Hole Spins in Active Galaxies Using Optical Reverberation Mapping
• Finding New High-Redshift Quasars by Asking the Neighbours

Cited by in corpus (9)

• The Infrared Medium-deep Survey. VIII. Quasar Luminosity Function at $z\sim 5$
• A Thirty-Four Billion Solar Mass Black Hole in SMSS J2157-3602, the Most Luminous Known Quasar
• The Infrared Medium-deep Survey. \Romannum{7}. Faint Quasars at $z\sim 5$ in the ELAIS-N1 Field
• Strong Lensed QSOs with Variability Detectable by LSST: How many are there?
• An Optically Faint Quasar Survey at z~5 in the CFHTLS Wide Field: Estimates of the Black Hole Masses and Eddington Ratios
• High-$z$ Universe probed via Lensing by QSOs (HULQ) I. Number Estimates of QSO-QSO and QSO-Galaxy Lenses
• Medium-band observation of the neutrino emitting blazar, TXS 0506+056
• The quasar luminosity function at $z\sim 5$ via deep learning and Bayesian information criterion
• High-$z$ Universe probed via Lensing by QSOs (HULQ) II. Deep GMOS spectroscopy of a QSO lens candidate