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Astronomische Nachrichten, Volume 341, Issue 3, Page 300-313, March 2020., 2020 Abstract We analyze emission line properties and their correlations for 18,043 type 1 active galactic nucleus (AGN) in the range of 0.02 ≤ z ≤ 0.8, based on Sloan Digital Sky Survey Data Release 14 data. We complement the data with photometric measurements from ROSAT, GALEX, 2MASS, and FIRST.
Irham Taufik Andika +2 more
wiley +1 more source
Broad absorption line variability in radio-loud quasars [PDF]
Monthly Notices of the Royal Astronomical Society, 2014 We investigate C IV broad absorption line (BAL) variability within a sample of 46 radio-loud quasars (RLQs), selected from SDSS/FIRST data to include both core-dominated (39) and lobe-dominated (7) objects. The sample consists primarily of high-ionization BAL quasars, and a substantial fraction have large BAL velocities or equivalent widths; their ...
Welling, C. A. +4 more
openaire +2 more sources
Spectral Variability in Radio-Loud Quasars [PDF]
Journal of Astrophysics and Astronomy, 2014 5 pages, 3 figures, accepted to JApA, conference proceeding paper for Variability of Blazars - From Jansky to Fermi (VBJF), Dec.
openaire +2 more sources
Near Infrared Micro-variability of Radio-loud Quasars [PDF]
Publications of the Astronomical Society of Australia, 2002 AbstractWe observed three AGN from the Parkes Half-Jansky Flat-spectrum Sample at near infrared (NIR) wavelengths to search for micro-variability. In one source, the blue quasar PKS 2243–123, good evidence for NIR micro-variability was found. In the other two sources, PKS 2240–260 and PKS 2233–148, both BL Lacertae objects, no such evidence of ...
Whiting, Matthew +2 more
openaire +2 more sources
Faint radio-loud quasars: clues to their evolution [PDF]
Monthly Notices of the Royal Astronomical Society, 2005 The quasar sample selected by cross-correlating the FIRST and the 2dF Quasar Redshift Surveys allows us to explore, for the first time, the faint end of the radio and optical luminosity functions up to z = 2.2. We find indications (~3 ) of a negative evolution for these faint sources at z > 1.8, both in radio and optical bands. This corresponds to
CIRASUOLO M. +2 more
openaire +2 more sources
3C 57 as an atypical radio-loud quasar: implications for the radio-loud/radio-quiet dichotomy [PDF]
Monthly Notices of the Royal Astronomical Society, 2015 Accepted for publication in MNRAS; 10 pages, 6 figures, 4 ...
Sulentic, J. W. +6 more
openaire +5 more sources
Intranight optical variability of BL Lacs, radio-quiet quasars and radio-loud quasars [PDF]
Monthly Notices of the Royal Astronomical Society, 2005 8 pages, 3 Postscript figures, Accepted for publication in MNRAS, uses mn2e ...
Stalin, C. S. +4 more
openaire +2 more sources
Astrometric Apparent Motion of High-redshift Radio Sources
The Astronomical Journal, 2023 Radio-loud quasars at high redshift ( z ≥ 4) are rare objects in the universe and rarely observed with Very Long Baseline Interferometry (VLBI). But some of them have flux density sufficiently high for monitoring of their apparent position.
Oleg Titov +12 more
doaj +1 more source
The host galaxies of three radio-loud quasars: 3C 48, 3C 345, and B2 1425+267 [PDF]
, 1999 Observations with the Wide-Field/Planetary Camera-2 of the Hubble Space Telescope (HST) are presented for three radio-loud quasars: 3C 48 (z=0.367), B2 1425+267 (z=0.366), and 3C 345 (z=0.594).
Akujor C. E. +13 more
core +2 more sources
GB:1508+5714: a radio-loud quasar with z = 4.30 and the space density of high-redshift radio-loud quasars [PDF]
Monthly Notices of the Royal Astronomical Society, 1995 We report the discovery of a radio loud quasar with a redshift of 4.30. This object, which is the first radio selected quasar with a redshift greater than four, was discovered during an observational investigation into the evolution of the luminosity function of radio loud quasars. Here we describe results based on a sample of ~300, flat spectrum radio
HOOK, IM +6 more
openaire +3 more sources