Results 1 to 10 of about 315 (120)
The Study of the Circumgalactic Medium with Quasar Pairs
The Astrophysical Journal Supplement Series, 2023 We have collected 10,025 foreground–background quasar pairs with projected distances d _p < 500 kpc from the large quasar catalog of the Sloan Digital Sky Survey DR16Q. We investigate the properties of the Mg ii absorption lines with W _r > 0.15 Å around
Zhi-Fu Chen +7 more
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Evidence of First Stars-enriched Gas in High-redshift Absorbers
The Astrophysical Journal, 2023 The first stars were born from chemically pristine gas. They were likely massive, and thus they rapidly exploded as supernovae, enriching the surrounding gas with the first heavy elements.
Andrea Saccardi +8 more
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The Astrophysical JournalThis study presents a detailed investigation of the broad absorption line (BAL) systems in the quasar SDSS J004613.54+010425.7 (hereafter J0046+0104), which makes characters of the simultaneous existence of line-locking and velocity shift signatures ...
Wei-Jian Lu, Ying-Ru Lin
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The Astrophysical JournalWe present an analysis of the coordinated velocity shifts observed in multiple C iv and Si iv broad absorption lines (BALs) in the quasar SDSS J113048.45+225206.6.
Wei-Jian Lu, Ying-Ru Lin
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The Astrophysical Journal Letters, 2023 The launch of JWST opens a new window for studying the connection between metal-line absorbers and galaxies at the end of the Epoch of Reionization.
Yunjing Wu +29 more
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Acceleration of C iv and Si iv Broad Absorption Lines in Quasar SDSS J140058.79+260619.4
The Astronomical JournalWe report the discovery of a velocity shift signature in the C iv and Si iv broad absorption lines (BALs) of the quasar SDSS J140058.79+260619.4 ( z _em = 2.351). From its two-epoch spectra, we find two BAL systems (systems A and B) in C iv and/or Si iv
Ying-Ru Lin, Wei-Jian Lu
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Reacceleration of a C iv Broad Absorption Line in Quasar SDSS J083817.00+295526.5
The Astrophysical JournalWe present a rare signature of reacceleration in a C iv broad absorption line (BAL) of the quasar SDSS J083817.00+295526.5. This quasar showcases three distinct BAL systems, labeled as systems A, B, and C.
Ying-Ru Lin, Wei-Jian Lu
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The Astrophysical Journal, 2023 Broad absorption line quasars are actively accreting supermassive black holes that have strong outflows characterized by broad absorption lines in their rest-UV spectra.
Kaylie S. Green +7 more
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The Astrophysical JournalQuasar outflows often consist of two clouds with velocity separations matching the doublet spacings of common UV resonance transitions, a phenomenon known as line locking, which is commonly observed in quasar spectra.
Chen Chen +5 more
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Tracking Outflow Using Line Locking (TOLL). I. The Case Study of Quasar J221531-174408
The Astrophysical JournalInvestigating line-locked phenomena within quasars is crucial for understanding the dynamics of quasar outflows, the role of radiation pressure in astrophysical flows, and the star formation history and metallicity of the early Universe.
Chen Chen +4 more
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