Results 101 to 110 of about 10,836 (194)

The Mass Density of Mg ii Absorbers from the Australian Dark Energy Survey

The Astrophysical Journal
We 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, Christopher W. Churchill, Glenn G. Kacprzak, Christopher Lidman, Susanna Guatelli, Sabine Bellstedt   +5 more
doaj   +1 more source

Rest-frame Optical Properties of Luminous 1.5

, 2015
We study the rest-frame optical properties of 74 luminous (L_bol=10^46.2-48.2 erg/s), 1 ...
Shen, Yue
core   +1 more source

Discovery of a Galaxy Cluster in the Foreground of the Wide-Separation Quasar Pair UM425

, 2005
We report the discovery of a cluster of galaxies in the field of UM425, a pair of quasars separated by 6.5arcsec. Based on this finding, we revisit the long-standing question of whether this quasar pair is a binary quasar or a wide-separation lens ...
Bolzonella M., Courbin F., Joshua N. Winn, Kayser R., Leopoldo Infante, Paul J. Green, Sebastian Lopez, Thomas L. Aldcroft   +7 more
core   +1 more source

Investigating Ionization in the Intergalactic Medium

The Astrophysical Journal
The 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, Anjali Ramesh, Sanchayeeta Borthakur   +2 more
doaj   +1 more source

The First High Redshift Quasar from Pan-STARRS

, 2011
We present the discovery of the first high redshift (z > 5.7) quasar from the Panoramic Survey Telescope and Rapid Response System 1 (Pan-STARRS1 or PS1).
Becker, Bill Sweeney, Chambers, Christopher Waters, De Rosa, Eric Morganson, Eugene Magnier, Fabian Walter, Fan, Fan, Fan, Fan, Fan, Freudling, Gisella De Rosa, Hans-Walter Rix, Heather Flewelling, Ian McGreer, Jiang, Jiang, Jochen Greiner, Kembhavi, Ken Chambers, Klaus Hodapp, Kurk, Kurk, Lang, Mortlock, Nick Kaiser, Paul Price, Price, Richards, Richards, Roberto Decarli, Skrutskie, Trump, Vanden Berk, Venemans, William Burgett, Willott, Willott, Xiaohui Fan, York   +42 more
core   +1 more source

Probing the He ii Reionization ERA via Absorbing C iv Historical Yield (HIERACHY). III. The C iv Absorber Catalog and Initial Results on Cosmic Abundance Evolution at z ≈ 3–5

The Astrophysical Journal
As part of the HIERACHY program, we collect the high signal-to-noise ratio and high-spectral resolution optical spectra of 25 quasars at z  ≈ 4–5 to constrain the C iv evolution at z  ≈ 3–5.
Xiaodi Yu, Zhijie Qu, Zheng Cai, Jiang-Tao Li, Huiyang Mao, Xin Wang   +5 more
doaj   +1 more source

Metal-strong Inflows at the Outer-galactic-scale of a Quasar

The Astrophysical Journal
We present an analysis of the absorption-line system in the Very Large Telescope/Ultraviolet and Visual Echelle Spectrograph spectrum at a redshift of z _a = 3.1448 associated with the quasar SDSS J122040.23+092326.96, whose systematic redshift is z _e =
Qiguo Tian, Lei Hao, Yipeng Zhou, Xiheng Shi, Tuo Ji, Peng Jiang, Lin Lin, Zhenya Zheng, Hongyan Zhou   +8 more
doaj   +1 more source

Measuring the Mean Free Path of H i Ionizing Photons at 3.2 ≤ z ≤ 4.6 with DESI Y1 Quasars

The Astrophysical Journal Letters
The mean free path of ionizing photons in the intergalactic medium (IGM; ${\lambda }_{{\rm{mfp}}}^{912}$ ) is a crucial quantity in modeling the ionization state of the IGM and the extragalactic ultraviolet background, and it is widely used in ...
Anning Gao, J. Xavier Prochaska, Zheng Cai, Siwei Zou, Cheng Zhao, Zechang Sun, S. Ahlen, D. Bianchi, D. Brooks, T. Claybaugh, A. de la Macorra, Arjun Dey, P. Doel, J. E. Forero-Romero, E. Gaztañaga, S. Gontcho A Gontcho, G. Gutierrez, K. Honscheid, S. Juneau, A. Kremin, P. Martini, A. Meisner, R. Miquel, J. Moustakas, A. Muñoz-Gutiérrez, J. A. Newman, I. Pérez-Ràfols, G. Rossi, E. Sanchez, M. Schubnell, D. Sprayberry, G. Tarlé, B. A. Weaver, H. Zou   +33 more
doaj   +1 more source

UEG Week 2025 Oral Presentations

United European Gastroenterology Journal, Volume 13, Issue S8, Page S7-S188, October 2025.
wiley   +1 more source

The Cosmic Ultraviolet Baryon Survey (CUBS). VII. On the Warm-hot Circumgalactic Medium Probed by O vi and Ne viii at 0.4 ≲ z ≲ 0.7

The Astrophysical Journal
This paper presents a newly established sample of 103 unique galaxies or galaxy groups at 0.4 ≲ z ≲ 0.7 from the Cosmic Ultraviolet Baryon Survey (CUBS) for studying the warm-hot circumgalactic medium (CGM) probed by both O vi and Ne viii absorption. The
Zhijie Qu, Hsiao-Wen Chen, Sean D. Johnson, Gwen C. Rudie, Fakhri S. Zahedy, David DePalma, Joop Schaye, Erin T. Boettcher, Sebastiano Cantalupo, Mandy C. Chen, Claude-André Faucher-Giguère, Jennifer I-Hsiu Li, John S. Mulchaey, Patrick Petitjean, Marc Rafelski   +14 more
doaj   +1 more source