High-frequency monitoring of quasars with absorption lines
نویسندگان
چکیده
منابع مشابه
The Frequency and Radio Properties of Broad Absorption Line Quasars
A sample of 67 Broad Absorption Line quasars (BALQSOs) from the Large Bright Quasar Survey (LBQS) is used to estimate the observed and intrinsic fraction of BAL quasars in optically– selected samples at intermediate (BJ ≃ 18.5) magnitudes. The observed BALQSO fraction in the redshift range 1.5 ≤ z ≤ 3.0 is 15± 3%. A well–determined, empirical, k–correction, to allow for the differences in the s...
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INTRODUCTION Observations of high-redshift quasars and absorption systems provide a rich data set on the early formation of structure in the universe. Theoretical and observational investigation of the physics leading to the formation of quasars and their environments can shed some light on early structure formation. In this contribution, I summarize briefly a few aspects of quasar physics that...
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ژورنال
عنوان ژورنال: Publications of the Astronomical Society of Japan
سال: 2017
ISSN: 0004-6264,2053-051X
DOI: 10.1093/pasj/psx060