Gemini GNIRS near-infrared spectroscopy of 50 quasars at z>~5.7

TY - JOUR

T1 - Gemini GNIRS near-infrared spectroscopy of 50 quasars at z>~5.7

AU - Shen, Yue

AU - Wu, Jin

AU - Jiang, Linhua

AU - Banados, Eduardo

AU - Fan, Xiaohui

AU - Ho, Luis C.

AU - Riechers, Dominik A.

AU - Strauss, Michael A.

AU - Venemans, Bram

AU - Vestergaard, Marianne

AU - Walter, Fabian

AU - Wang, Feige

AU - Willott, Chris

AU - Wu, Xue-Bing

AU - Yang, Jinyi

PY - 2019/3/1

Y1 - 2019/3/1

N2 - We report initial results from a large Gemini program to observe z ≥ 5.7 quasars with GNIRS near-IR spectroscopy. Our sample includes 50 quasars with simultaneous ∼0.85-2.5 μm spectra covering the rest-frame ultraviolet and major broad emission lines from Lyα to Mg ii. We present spectral measurements for these quasars and compare with their lower redshift counterparts at z = 1.5-2.3. We find that when quasar luminosity is matched, there are no significant differences between the rest-UV spectra of z ≥ 5.7 quasars and the low-z comparison sample. High-z quasars have similar continuum and emission line properties and occupy the same region in the black hole mass and luminosity space as the comparison sample, accreting at an average Eddington ratio of ∼0.3. There is no evidence for super-Eddington accretion or hypermassive (>10 10 M o ) black holes within our sample. We find a mild excess of quasars with weak C iv lines relative to the control sample. Our results, corroborating earlier studies but with better statistics, demonstrate that these high-z quasars are already mature systems of accreting supermassive black holes operating with the same physical mechanisms as those at lower redshifts.

AB - We report initial results from a large Gemini program to observe z ≥ 5.7 quasars with GNIRS near-IR spectroscopy. Our sample includes 50 quasars with simultaneous ∼0.85-2.5 μm spectra covering the rest-frame ultraviolet and major broad emission lines from Lyα to Mg ii. We present spectral measurements for these quasars and compare with their lower redshift counterparts at z = 1.5-2.3. We find that when quasar luminosity is matched, there are no significant differences between the rest-UV spectra of z ≥ 5.7 quasars and the low-z comparison sample. High-z quasars have similar continuum and emission line properties and occupy the same region in the black hole mass and luminosity space as the comparison sample, accreting at an average Eddington ratio of ∼0.3. There is no evidence for super-Eddington accretion or hypermassive (>10 10 M o ) black holes within our sample. We find a mild excess of quasars with weak C iv lines relative to the control sample. Our results, corroborating earlier studies but with better statistics, demonstrate that these high-z quasars are already mature systems of accreting supermassive black holes operating with the same physical mechanisms as those at lower redshifts.

KW - Astrophysics - Astrophysics of Galaxies

KW - Astrophysics - Cosmology and Nongalactic Astrophysics

U2 - 10.3847/1538-4357/ab03d9

DO - 10.3847/1538-4357/ab03d9

M3 - Journal article

SN - 0004-637X

VL - 873

JO - Astrophysical Journal

JF - Astrophysical Journal

M1 - 35

ER -