Results 21 to 30 of about 719 (181)
On the masses of black holes in radio-loud quasars [PDF]
Monthly Notices of the Royal Astronomical Society, 2001 The central black-hole masses of a sample of radio-loud quasars are estimated by using the data of $H_β$ line-width and the optical continuum luminosity. The vast majority of the quasars in this sample have black-hole masses larger than $10^{8} M_{\odot}$, while a few quasars may contain relatively smaller black-holes.
Gu, Minfeng, Cao, Xinwu, Jiang, D. R.
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
The Nature of the IMBH Candidate CXO J133815.6+043255: High-frequency Radio Emission
The Astrophysical Journal, 2023 The ultraluminous X-ray source CXO J133815.6+043255 is a strong candidate for a bona fide intermediate-mass black hole residing in the outskirts of NGC 5252.
Krista Lynne Smith +2 more
doaj +1 more source
Metal Content in Relativistically Jetted and Radio-Quiet Quasars in the Main Sequence Context
Galaxies, 2023 The optical and UV properties of radio-quiet (RQ) and radio-loud (RL, relativistically “jetted”) active galactic nuclei (AGN) are known to differ markedly; however, it is still unclear what is due to a sample selection and what is associated with ...
Paola Marziani +3 more
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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
CONSTRAINING THE RADIO-LOUD FRACTION OF QUASARS ATz> 5.5 [PDF]
The Astrophysical Journal, 2015 Radio-loud Active Galactic Nuclei at z~2-4 are typically located in dense environments and their host galaxies are among the most massive systems at those redshifts, providing key insights for galaxy evolution. Finding radio-loud quasars at the highest accessible redshifts (z~6) is important to study their properties and environments at even earlier ...
E. Bañados +20 more
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The Pan-STARRS1 z > 5.6 Quasar Survey. II. Discovery of 55 Quasars at 5.6 < z < 6.5
The Astrophysical Journal Supplement Series, 2023 The identification of bright quasars at z ≳ 6 enables detailed studies of supermassive black holes, massive galaxies, structure formation, and the state of the intergalactic medium within the first billion years after the Big Bang.
Eduardo Bañados +22 more
doaj +1 more source
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
IRAS observations of radio-quiet and radio-loud quasars
The Astrophysical Journal, 1984 Observations from 12 to 100 microns are presented of two radio-quiet and three radio-loud quasars. Over this wavelength range, all five have grossly similar continuum energy distributions. The continua of the radio-loud quasars are consistent with synchrotron radiation.
G. Neugebauer +9 more
openalex +4 more sources
The optical variability of radio-loud quasars [PDF]
Proceedings of the International Astronomical Union, 2012 AbstractThe optical variability of a sample of 44 FSRQs and 18 SSRQs in the SDSS stripe 82 region is investigated by using the multi-epoch data covering nine years. The variabilities are clearly detected in each source with the amplitude in r band, from 0.18 to 3.46 mag.
Minfeng Gu, Y. L. Ai
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