Large-scale homogeneity in the distribution of quasars in the Hercules-Corona Borealis Great Wall region [PDF]
Serbian Astronomical Journal, 2022 In light of recent debates on the existence of a gigaparsec-scale structure traced by gamma-ray bursts, namely the Hercules-Corona Borealis Great Wall (HCBGW), we revisit large-scale homogeneity in the spatial distribution of quasars. Our volume-
Fujii Hirokazu
doaj +1 more source
Spatially resolved rotation of the broad-line region of a quasar at sub-parsec scale [PDF]
Nature, 2018 The broadening of atomic emission lines by high-velocity motion of gas near accreting supermassive black holes is an observational hallmark of quasars1.
G. Collaboration
semanticscholar +1 more source
Proceedings of the International Astronomical Union, 2014 AbstractAlthough the extragalactic nature of 3C 48 and other quasi stellar radio sources was discussed as early as 1960 by John Bolton and others, it was rejected largely because of preconceived ideas about what appeared to be unrealistically high radio and optical luminosities.
openaire +3 more sources
Statistics of Galactic-scale Quasar Pairs at Cosmic Noon
The Astrophysical Journal, 2023 The statistics of galactic-scale quasar pairs can elucidate our understanding of the dynamical evolution of supermassive black hole (SMBH) pairs, the duty cycles of quasar activity in mergers, or even the nature of dark matter, but they have been ...
Yue Shen +10 more
doaj +1 more source
Changing-look Quasar Candidates: First Results from Follow-up Spectroscopy of Highly Optically Variable Quasars [PDF]
Astrophysical Journal, 2018 Active galactic nuclei (AGNs) that show strong rest-frame optical/UV variability in their blue continuum and broad line emission are classified as changing-look AGN, or at higher luminosities, changing-look quasars (CLQs).
C. MacLeod +17 more
semanticscholar +1 more source
Imprints of the super-Eddington accretion on the quasar clustering
, 2017 Super-Eddington mass accretion has been suggested as an efficient mechanism to grow supermassive black holes (SMBHs). We investigate the imprint left by the radiative efficiency of the super-Eddington accretion process on the clustering of quasars using ...
Enoki, Motohiro +7 more
core +1 more source
Modeling the HeII Transverse Proximity Effect: Constraints on Quasar Lifetime and Obscuration
, 2017 The HeII transverse proximity effect - enhanced HeII Ly{\alpha} transmission in a background sightline caused by the ionizing radiation of a foreground quasar - offers a unique opportunity to probe the emission properties of quasars, in particular the ...
Davies, Frederick B. +5 more
core +1 more source
Microlensing variability in the gravitationally lensed quasar Q2237+0305 = the Einstein Cross, I. Spectrophotometric monitoring with the VLT [PDF]
, 2008 We present the results of the first long-term (2.2 years) spectroscopic monitoring of a gravitationally lensed quasar, namely the Einstein Cross Q2237+0305.
A. Eigenbrod +62 more
core +2 more sources
A CATALOG OF QUASAR PROPERTIES FROM SLOAN DIGITAL SKY SURVEY DATA RELEASE 7 [PDF]
, 2010 We present a compilation of properties of the 105,783 quasars in the Sloan Digital Sky Survey Data Release 7 (DR7) quasar catalog. In this product, we compile continuum and emission line measurements around the Hα, Hβ, Mg ii, and C iv regions, as well as
Yue Shen +12 more
semanticscholar +1 more source
A Mid-IR Selected Changing-look Quasar and Physical Scenarios for Abrupt AGN Fading [PDF]
Astrophysical Journal, 2018 We report a new changing-look quasar, WISE J105203.55+151929.5 at z = 0.303, found by identifying highly mid-IR-variable quasars in the Wide-field Infrared Survey Explorer (WISE)/Near-Earth Object WISE Reactivation (NEOWISE) data stream.
D. Stern +13 more
semanticscholar +1 more source