Results 1 to 10 of about 111,891 (295)
A SPectroscopic Survey of Biased Halos in the Reionization Era (ASPIRE): A First Look at the Rest-frame Optical Spectra of z > 6.5 Quasars Using JWST [PDF]
The Astrophysical Journal Letters, 2023 Studies of rest-frame optical emission in quasars at z > 6 have historically been limited by the wavelengths accessible by ground-based telescopes. The James Webb Space Telescope (JWST) now offers the opportunity to probe this emission deep into the ...
Jinyi Yang +55 more
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Detecting and Characterizing Young Quasars. III. The Impact of Gravitational Lensing Magnification
The Astrophysical Journal, 2023 We test the impact of gravitational lensing on the lifetime estimates of seven high-redshift quasars at redshift z ≳ 6. The targeted quasars are identified by their small observed proximity zone sizes, which indicate extremely short quasar lifetimes ( t ...
Minghao Yue +10 more
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The Astrophysical Journal Supplement Series, 2023 We report the fourth installment in the series of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) quasar survey, which includes quasars observed between 2017 September and 2021 June.
Jun-Jie Jin +12 more
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Investigating Gravitationally Lensed Quasars Observable by Nancy Grace Roman Space Telescope
Galaxies, 2023 In this work, we investigate the possibility of observing quasars, particularly lensed quasars, by the Nancy Grace Roman Space Telescope (Roman).
Lindita Hamolli +3 more
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Frontiers in Astronomy and Space Sciences, 2022 Given their extremely large distances and small apparent sizes, quasars are generally considered as objects with near-zero parallax and proper motion.
Qi-Qi Wu +15 more
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Extreme Quasars as Distance Indicators in Cosmology
Frontiers in Astronomy and Space Sciences, 2020 Quasars accreting matter at very high rates (known as extreme Population A [xA] quasars, possibly associated with super-Eddington accreting massive black holes) may provide a new class of distance indicators covering cosmic epochs from present day up to ...
Deborah Dultzin +10 more
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Galaxies, 2021 The radiative and jet power in active galactic nuclei is generated by accretion of material on to supermassive galactic-centre black holes. For quasars, where the radiative power is by definition very high, objects with high radio luminosities form 10 ...
Gülay Gürkan +5 more
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A Sample of Quasars with Strong Nitrogen Emission Lines from the Sloan Digital Sky Survey [PDF]
, 2008 We report on 293 quasars with strong NIV] lambda 1486 or NIII] lambda 1750 emission lines (rest-frame equivalent width > 3 \AA) at 1.7 < z < 4.0 selected from the Sloan Digital Sky Survey (SDSS) Fifth Data Release.
Fan, Xiaohui +2 more
core +2 more sources
The Small-Scale Environment of Quasars [PDF]
, 2006 Where do quasars reside? Are quasars located in environments similar to those of typical L* galaxies, and, if not, how do they differ? An answer to this question will help shed light on the triggering process of quasar activity.
Bahcall, Neta +3 more
core +1 more source
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
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