Results 1 to 10 of about 224 (129)
A Candidate Dual QSO at Cosmic Noon
The Astrophysical Journal Letters, 2023 We report the discovery of a candidate dual QSO at z = 1.889, a redshift that is in the era known as “cosmic noon” where most of the universe’s black hole and stellar mass growth occurred.
Eilat Glikman +8 more
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Statistics of Galactic-scale Quasar Pairs at Cosmic Noon
The Astrophysical Journal, 2023 The statistics of galactic-scale quasar pairs can elucidate our understanding of the dynamical evolution of supermassive black hole (SMBH) pairs, the duty cycles of quasar activity in mergers, or even the nature of dark matter, but they have been ...
Yue Shen +10 more
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A Catalog of Candidate Double and Lensed Quasars from Gaia and WISE Data
The Astrophysical Journal Supplement Series, 2022 Making use of strong correlations between closely separated multiple or double sources and photometric and astrometric metadata in Gaia Early Data Release 3 (EDR3), we generate a catalog of candidate double- and multiply imaged lensed quasars and active ...
Valeri V. Makarov, Nathan J. Secrest
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The Astronomical Journal, 2023 We present the first results from a new survey for high-redshift ( z ≳ 5) gravitationally lensed quasars and close quasar pairs. We carry out candidate selection based on the colors and shapes of objects in public imaging surveys, then conduct follow-up ...
Minghao Yue +3 more
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Quasar Luminosity Function at z = 7
The Astrophysical Journal Letters, 2023 We present the quasar luminosity function (LF) at z = 7, measured with 35 spectroscopically confirmed quasars at 6.55 < z < 7.15. The sample of 22 quasars from the Subaru High- z Exploration of Low-Luminosity Quasars (SHELLQs) project, combined with 13 ...
Yoshiki Matsuoka +43 more
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The Astrophysical Journal Letters, 2023 We report Hubble Space Telescope (HST) Wide Field Camera 3 deep IR (F160W) imaging of SDSS J1608+2716. This system, located at a redshift of z = 2.575, was recently reported as a triple-quasar candidate with subarcsecond separations (∼0.″25) based on ...
Junyao Li +7 more
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The Astrophysical Journal, 2023 Dual quasars at small physical separations are an important precursor phase of galaxy mergers, ultimately leading to the coalescence of the two supermassive black holes.
Arran C. Gross +10 more
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The Astrophysical Journal, 2023 Dual and off-nucleus active supermassive black holes are expected to be common in the hierarchical structure formation paradigm, but their identification at parsec scales remains a challenge due to strict angular resolution requirements.
Yu-Ching Chen +7 more
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Blueshifted Fe ii and Balmer Broad Emission lines in a Reddened Quasar
The Astrophysical Journal, 2023 We present detailed analysis of the optical and near-infrared spectrum of the reddened radio-loud quasar F2M J154043.74+492323.9 with strong optical Fe ii emission of ${R}_{4570}\equiv \tfrac{\mathrm{Fe}\,{\rm\small{II}}\lambda \lambda \,4434,4684}{{\rm ...
Yipeng Zhou +3 more
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The Pan-STARRS1 z > 5.6 Quasar Survey. III. The z ≈ 6 Quasar Luminosity Function
The Astrophysical Journal, 2023 We present the z ≈ 6 type-1 quasar luminosity function (QLF), based on the Pan-STARRS1 (PS1) quasar survey. The PS1 sample includes 125 quasars at z ≈ 5.7–6.2, with −28 ≲ M _1450 ≲ −25.
Jan-Torge Schindler +11 more
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