Quasars Probing Quasars. I. Optically Thick Absorbers near Luminous Quasars
نویسندگان
چکیده
منابع مشابه
Quasars Probing Quasars I: Optically Thick Absorbers near Luminous Quasars
With close pairs of quasars at different redshifts, a background quasar sightline can be used to study a foreground quasar’s environment in absorption. We search 149 moderate resolution background quasar spectra, from Gemini, Keck, the MMT, and the SDSS to survey Lyman Limit Systems (LLSs) and Damped Lyα systems (DLAs) in the vicinity of 1.8 < z < 4.0 luminous foreground quasars. A sample of 27...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2006
ISSN: 0004-637X,1538-4357
DOI: 10.1086/507069