Results 11 to 20 of about 83,297 (253)
The Astrophysical Journal Supplement Series, 2023 Since their first discovery, quasars have been essential probes of the distant Universe. However, due to our limited knowledge of its nature, predicting the intrinsic quasar continua has bottlenecked their usage.
Zechang Sun, Yuan-Sen Ting, Zheng Cai
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A Thirty-Four Billion Solar Mass Black Hole in SMSS J2157-3602, the Most Luminous Known Quasar [PDF]
, 2020 From near-infrared spectroscopic measurements of the MgII emission line doublet, we estimate the black hole (BH) mass of the quasar, SMSS J215728.21-360215.1, as being (3.4 +/- 0.6) x 10^10 M_sun and refine the redshift of the quasar to be z=4.692.
Bian, Fuyan +5 more
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Do Quasars Lens Quasars? [PDF]
The Astrophysical Journal, 1997 If the unexpectedly high frequency of quasar pairs with very different component redshifts is due to the lensing of a population of background quasars by the foreground quasar, typical lens masses must be $\sim10^{12}M_{\sun}$ and the sum of all such quasar lenses would have to contain $\sim0.005$ times the closure density of the Universe.
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Two Close Separation Quasar-Quasar Pairs in the Large Bright Quasar Survey [PDF]
The Astronomical Journal, 1998 Accepted for publication in the Astronomical Journal, Paper, 4 Figures + 1 ...
Hewett, Paul C. +3 more
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magazén, 2022 The city is a set of arbitrary visual experiences dispersed in time that must necessarily be integrated. In studying the absences, Bruno Toscano writes that “the city would appear to us in a less verisimilar facies if we resigned ourselves to consider
Farina, Arianna
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EXTENDED SCATTERING ENVELOPE IN THE Q2237+0305 QUASAR
Radio Physics and Radio Astronomy, 2019 Purpose: Studying the accretion disc structure in the Q2237+0305 gravitationally lensed quasar in optical wavelengths; estimation of parameters of the matter accretion regime onto a central black hole.
L. A. Berdina +2 more
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Improved redshifts for SDSS quasar spectra [PDF]
, 2010 A systematic investigation of the relationship between different redshift estimation schemes for more than 91000 quasars in the Sloan Digital Sky Survey (SDSS) Data Release 6 (DR6) is presented.
Abazajian +30 more
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Autosomal Dominant Leukodystrophy: A Disease of the Nuclear Lamina
Frontiers in Cell and Developmental Biology, 2019 The nuclear lamina is a fibrous meshwork of proteins found adjacent to the inner nuclear membrane that plays a critical role in the maintenance of nuclear architecture.
Quasar S. Padiath
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Circum-Galactic Medium in the Halo of Quasars
Frontiers in Astronomy and Space Sciences, 2017 The properties of circum-galactic gas in the halo of quasar host galaxies are investigated analyzing Mg II 2800 and C IV 1540 absorption-line systems along the line of sight close to quasars.
Riccardo Ottolina +6 more
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Symposium - International Astronomical Union, 1994 I review recent results for quasars and discuss how they are related to activity in galaxies. Topics included are studies of quasar host galaxies with HST; searches for quasars in the Hubble Deep Field; evolution of the quasar luminosity function; news highlights from astro-ph; and current observational research problems and their relation to ...
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