Results 81 to 90 of about 1,319 (176)
The Signatures of Density Fluctuations and Mixing Gas in Circumgalactic Absorption Systems
The Astrophysical JournalWe investigate the prospects for detecting and constraining density and temperature inhomogeneities in the circumgalactic medium using absorption measurements of metal ions.
Yakov Faerman +3 more
doaj +1 more source
The Qz5 Survey. II. Metallicity Evolution of Damped Lyα Systems Out to z ∼ 5
The Astrophysical JournalDamped Ly α absorbers (DLAs) are the highest H i column density ( N _H I ) absorption line systems detected in the spectra of background quasars. DLAs dominate the neutral gas content of the Universe (Ω _HI ) and are used to measure the metallicity ...
M. E. Wisz +12 more
doaj +1 more source
The COS-Holes Survey: Connecting Galaxy Black Hole Mass with the State of the CGM
The Astrophysical JournalWe present an analysis of Hubble Space Telescope COS/G160M observations of C IV in the inner circumgalactic medium (CGM) of a novel sample of eight z ∼ 0, L ≈ L ^⋆ galaxies, paired with UV-bright QSOs at impact parameters ( R _proj ) between 25 and 130 ...
Samantha L. Garza +11 more
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One H2 molecule per ten million H atoms reveals sub-parsec-scale cold overdensities at z ∼ 4★
Astronomy & AstrophysicsWe present the detection and analysis of H2 absorption at z = 4.24 towards the bright quasar J 0007−5705, which was observed with the Very Large Telescope as part of the ESPRESSO QUasar Absorption Line Survey (EQUALS). The high resolving power of R ≈ 120
Noterdaeme P. +13 more
doaj +1 more source
Kinematics of Circumgalactic O vi Gas and Disk Rotation of z ≈ 0.2 Star-forming Galaxies
The Astrophysical JournalQuasar sightline observations reveal that low ionization state gas corotates with the galaxy disk and often at subcentrifugal velocities, suggesting that the gas is spiraling toward the galaxy disk.
Stephanie H. Ho +4 more
doaj +1 more source
Circumnuclear Gas of a Quasar in Absorption and Emission Lines
The Astrophysical JournalWe present a detailed analysis of the unusual absorption- and emission-line spectrum of the quasar SDSS J074850.39+442439.0 (hereafter J0748+4424) at a redshift of z = 2.18. The archival SDSS optical spectrum is abundant in narrow absorption lines (NALs)
Xuejie Dai +12 more
doaj +1 more source
The Astrophysical JournalHow do galaxies of different luminosities contribute to the metal absorber populations of varying species and strength? We present our analysis of the predicted metal contributions from galaxies as observed in quasar absorption line spectra during the ...
Samir Kušmić +3 more
doaj +1 more source
The Distance to the Magellanic Stream: Constraints from Optical Absorption along Stellar Sight Lines
The Astrophysical JournalThe Magellanic Stream is a large tail of neutral and ionized gas originating from tidal and hydrodynamical interactions between the Magellanic Clouds as they orbit the Milky Way (MW).
Sapna Mishra +4 more
doaj +1 more source
The Mass Density of Mg ii Absorbers from the Australian Dark Energy Survey
The Astrophysical JournalWe present an all-southern sky survey for Mg ii λλ 2796, 2803 doublet absorbers in 951 z < 4 active galactic nucleus/quasar spectra from the Australian Dark Energy Survey.
Asif Abbas +5 more
doaj +1 more source
Investigating Ionization in the Intergalactic Medium
The Astrophysical JournalThe intergalactic medium (IGM) contains >50% of the baryonic mass of the Universe, yet the mechanisms responsible for keeping the IGM ionized have not been fully explained.
Brad Koplitz +2 more
doaj +1 more source