A Population of Dust-rich Quasars at z ~ 1.5 [PDF]
, 2012 We report Herschel SPIRE (250, 350, and 500 μm) detections of 32 quasars with redshifts 0.5 ≤z < 3.6 from the Herschel Multi-tiered Extragalactic Survey (HerMES).
Bergeron, Jacqueline +21 more
core +3 more sources
Shedding New Light on Weak Emission-line Quasars in the C iv–Hβ Parameter Space
The Astrophysical Journal, 2023 Weak emission-line quasars (WLQs) are a subset of type 1 quasars that exhibit extremely weak Ly α + N v λ 1240 and/or C iv λ 1549 emission lines. We investigate the relationship between emission-line properties and accretion rate for a sample of 230 ...
Trung Ha +22 more
doaj +1 more source
Determining Central Black Hole Masses in Distant Active Galaxies and Quasars. II. Improved Optical and UV Scaling Relationships [PDF]
, 2002 We present four improved empirical relationships useful for estimating the central black hole mass in nearby AGNs and distant luminous quasars alike using either optical or UV single-epoch spectroscopy.
M. Vestergaard, B. Peterson
semanticscholar +1 more source
Exploring Reionization-era Quasars. III. Discovery of 16 Quasars at 6.4 ≲ z ≲ 6.9 with DESI Legacy Imaging Surveys and the UKIRT Hemisphere Survey and Quasar Luminosity Function at z ∼ 6.7 [PDF]
Astrophysical Journal, 2018 This is the third paper in a series aimed at finding reionization-era quasars with the combination of DESI Legacy imaging Surveys (DELS), the Pan-STARRS1 (PS1) Survey, and near-infrared imaging surveys, such as the UKIRT Hemisphere Survey (UHS), as well ...
Feige Wang +24 more
semanticscholar +1 more source
Quasar Luminosity Function at z = 7
The Astrophysical Journal Letters, 2023 We present the quasar luminosity function (LF) at z = 7, measured with 35 spectroscopically confirmed quasars at 6.55 < z < 7.15. The sample of 22 quasars from the Subaru High- z Exploration of Low-Luminosity Quasars (SHELLQs) project, combined with 13 ...
Yoshiki Matsuoka +43 more
doaj +1 more source
Detecting and Characterizing Young Quasars. I. Systemic Redshifts and Proximity Zone Measurements
Astrophysical Journal, 2020 In a multiwavelength survey of 13 quasars at 5.8 ≲ z ≲ 6.5, which were preselected to be potentially young, we find five objects with extremely small proximity zone sizes that may imply UV-luminous quasar lifetimes of ≲100,000 yr.
A. Eilers +14 more
semanticscholar +1 more source
The FIRST Bright Quasar Survey III. The South Galactic Cap [PDF]
, 2001 We present the results of an extension of the FIRST Bright Quasar Survey (FBQS) to the South Galactic cap, and to a fainter optical magnitude limit. Radio source counterparts with SERC R magnitudes brighter than 18.9 which meet the other FBQS criteria ...
Chris D. Impey +12 more
core +2 more sources
Dust-Deficient Palomar-Green Quasars and the Diversity of AGN Intrinsic IR Emission
, 2017 To elucidate the intrinsic broadband infrared (IR) emission properties of active galactic nuclei (AGNs), we analyze the spectral energy distributions (SEDs) of 87 ...
Lyu, Jianwei, Rieke, G. H., Shi, Yong
core +1 more source
Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs). VIII. A less biased view of the early co-evolution of black holes and host galaxies [PDF]
Nippon Tenmon Gakkai obun kenkyu hokoku, 2019 We present ALMA [C ii] line and far-infrared (FIR) continuum observations of three $z \gt 6$ low-luminosity quasars ($M_{\rm 1450} \gt -25$ mag) discovered by our Subaru Hyper Suprime-Cam (HSC) survey.
T. Izumi +26 more
semanticscholar +1 more source
Exploratory Chandra Observations of the Three Highest Redshift Quasars Known
, 2002 We report on exploratory Chandra observations of the three highest redshift quasars known (z = 5.82, 5.99, and 6.28), all found in the Sloan Digital Sky Survey.
Bing Chen +16 more
core +1 more source