Results 191 to 200 of about 1,391,040 (211)
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Intrinsic variations of the double quasar 0957 + 56 AB
Nature, 1981Spectroscopic evidence strongly suggests that the two quasars 0957 + 56 A and B are images produced by the gravitational lensing of a single distant quasar (at z = 1.41) by a giant elliptical galaxy and its attendant cluster (at z = 0.36)1–6. It has also been suggested that the quasar is an intrinsic variable7,8.
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The nature of double-peaked lines in Sy 1 and quasars
AIP Conference Proceedings, 2001We have analyzed the Lyα, Hβ and Hα line profiles of three active galactic nuclei: quasar 3C390.3 and two Seyfert 1 galaxies; Akn 120 and III Zw2. The blue- and red-shifted broad Gaussian components which are present in all considered 3C390.3 and Akn 120 lines cannot be explained by an accretion disk model because of the lines’ variation on longer time-
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Estimation of model parameters in the selected double imaged quasars
Astronomical and Astrophysical TransactionsThis article presents the results of modeling based on observations of the gravitationally lensed quasars SDSS J0806+2006 and SDSS J2124+1632 observed at the Maidanak Observatory in 2017-2022 and 2018-2022. The value of the Hubble constant H0= 61.4±7 for the SDSS J0806+2006 GLK is estimated, and the redshift of the lensing galaxy for the SDSS J2124 ...
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Double peaked broad line profiles — edge on accretion disks or double quasar nuclei?
2008It is pointed out that a significant fraction (over 50%) of quasars do not show smooth symmetric “logarithmic” broad line profiles, but instead show double broad line peaks, usually unequal in brightness, always one blueshifted and one redshifted relative to the systemic velocity.
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The prevalence of Fanaroff-Riley type I radio quasars
Monthly Notices of the Royal Astronomical Society, 2007Ian Heywood +2 more
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