Results 31 to 40 of about 1,747 (185)
The Astrophysical Journal, 2023 We present, for the first time, dark matter halo (DMH) mass measurement of quasars at z ∼ 6 based on a clustering analysis of 107 quasars. Spectroscopically identified quasars are homogeneously extracted from the Hyper Suprime-Cam Strategic Survey ...
Junya Arita +12 more
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The Astrophysical Journal, 2023 We explore reprocessing models for a sample of 17 hypervariable quasars, taken from the Sloan Digital Sky Survey Reverberation Mapping project, which all show coordinated optical luminosity hypervariability with amplitudes of factors ≳2 between 2014 and ...
Tatsuya Akiba +7 more
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Exploring galaxy mass profiles in strongly lensed quasars with upcoming Roman Space Telescope observations [PDF]
EPJ Web of ConferencesStrong gravitational lensing of quasars is a powerful tool for probing cosmological parameters, tracing galaxy evolution, and investigating the internal structure of quasars.
Guliqani Esmeralda +2 more
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Some Constraints on Quasar Progenitors and Quasar Evolution [PDF]
Symposium - International Astronomical Union, 1986 There is strong evidence that quasars are powered by the gravitational energy released by in fall of matter into a compact supermassive object which is most likely a black hole with mass M>106 to 109MO. The question then arises as to how such massive black holes came to be formed. What sort of objects were the progenitors?
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Finding Multiply Lensed and Binary Quasars in the DESI Legacy Imaging Surveys
The Astrophysical Journal Supplement Series, 2023 The time delay between multiple images of strongly lensed quasars is a powerful tool for measuring the Hubble constant ( H _0 ). To achieve H _0 measurements with higher precision and accuracy using the time delay, it is crucial to expand the sample of ...
C. Dawes +6 more
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Constraining the anisotropy of the Universe with the X-ray and UV fluxes of quasars
European Physical Journal C: Particles and Fields, 2021 We test the anisotropy in the Finslerian cosmological model with the X-ray and ultraviolet (UV) fluxes of quasars. The 2015 and 2020 compilations of quasars are used in the cosmological constraints.
Dong Zhao, Jun-Qing Xia
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UCHL3 Regulates Subgenomic Flaviviral RNA Condensates to Promote Virus Propagation
Advanced Science, EarlyView.ABSTRACT Flavivirus subgenomic RNAs (sfRNAs) antagonise antiviral defences, yet how sfRNAs are organized and maintained in cells remains poorly understood. Here we identify ubiquitin C‐terminal hydrolase L3 (UCHL3) as a post‐translational regulator of flavivirus sfRNA stability and function.
Oscar Trejo‐Cerro +7 more
wiley +1 more source
The Infrared Traced Star Formation Rates of Associated Absorption Lines Quasars
The Astrophysical JournalSome optically selected quasars exhibit Mg ii- associated absorption lines (AALs), and their origin remains unclear. In this paper, we compile a sample of 1769 quasars, with or without Mg ii AALs, of which 1689 are far-infrared (FIR) detected quasars and
Zhe-Geng Chen +6 more
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Gaia Space Mission and Quasars
Frontiers in Astronomy and Space Sciences, 2017 Quasars are often considered to be point-like objects. This is largely true and allows for an excellent alignment of the optical positional reference frame of the ongoing ESA mission Gaia with the International Celestial Reference Frame.
Tomaž Zwitter
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A Hubble Diagram for Quasars [PDF]
Frontiers in Astronomy and Space Sciences, 2018 The cosmological model is at present not tested between the redshift of the farthest observed supernovae (z ~ 1.4) and that of the Cosmic Microwave Background (z ~ 1,100). Here we introduce a new method to measure the cosmological parameters: we show that quasars can be used as "standard candles" by employing the non-linear relation between their ...
Susanna Bisogni +4 more
openaire +5 more sources