312 citations · 1.8k across the 39 of their papers we have counts for
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Subaru Telescope limits on cosmological variations in the fine-structure constant
Michael T. Murphy, Kathy L. Cooksey
Previous, large samples of quasar absorption spectra have indicated some evidence for relative variations in the fine-structure constant () across the sky. However, they were…
Mg II Absorption at 2<z<7 with Magellan/FIRE, III. Full Statistics of Absorption Towards 100 High-Redshift QSOs
Shi-Fan S. Chen, Robert A. Simcoe, Paul Torrey +12
We present final statistics from a survey for intervening MgII absorption towards 100 quasars with emission redshifts between and . Using infrared spectra from Mag…
Halo Masses of MgII absorbers at z\sim 0.5 from SDSS DR7
Jean-Rene Gauthier, Hsiao-Wen Chen, Kathy L. Cooksey +3
We present the cross-correlation function of MgII absorbers with respect to a volume-limited sample of luminous red galaxies (LRGs) at z=0.45-0.60 using the largest MgII absorber s…
Precious Metals in SDSS Quasar Spectra II: Tracking the Evolution of Strong, 0.4 < z < 2.3 MgII Absorbers with Thousands of Systems
Eduardo N. Seyffert, Kathy L. Cooksey, Robert A. Simcoe +3
We have performed an analysis of over 34,000 MgII doublets at 0.36 < z < 2.29 in Sloan Digital Sky Survey (SDSS) Data-Release 7 quasar spectra; the catalog, advanced data products,…
Extremely metal-poor gas at a redshift of 7
Robert A. Simcoe, Peter W. Sullivan, Kathy L. Cooksey +3
In typical astrophysical environments, the abundance of heavy elements ranges from 0.001 to 2 times the solar concentration. Lower abundances have been seen in select stars in the…
An Independent Measurement of the Incidence of MgII Absorbers along Gamma-Ray Burst Sightlines: the End of the Mystery?
A. Cucchiara, J. X. Prochaska, G. Zhu +15
In 2006, Prochter et al. reported a statistically significant enhancement of very strong Mg II absorption systems intervening the sightlines to gamma-ray bursts (GRBs) relative to…