• Corpus ID: 93514571

Quasar absorption lines

  title={Quasar absorption lines},
  author={Peter Goldreich and Wallace L. W. Sargent},
" Analyzing a spectrum is exactly like doing a crossword puzzle, but when you get through with it, you call the answer research. " – Henry Norris Russell. The absorption lines observed in quasar spectra have given us a detailed picture of the in-tergalactic medium and the metal abundance and kinematics of high redshift galaxies. In this review, we present an introduction to the field, starting with the techniques used for interpreting absorption line spectra. We then survey the observational… 
QSO Absorption Line Systems as a Probe of Galaxies Like the Milky Way
Quasar absorption lines provide detailed information on the chemical, kinematic, and ionization conditions in galaxies and their environments, and provide a means for studying the evolution of these
The Kinematic Composition of Mg ii Absorbers 1
The study of galaxy evolution using quasar absorption lines requires an understanding of what components of galaxies and their surroundings are contributing to the absorption in various transitions.
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We challenge the conventional view that the majority of Mg II /Lyman limit absorbers are extended halos of galaxies comprised of “clouds” with near–unity covering factor. The gaseous disks of spiral
Complex Mg II Absorption in the Outer Disk of M61
The increasing availability of high-quality spectra of QSO absorption-line systems at resolutions of only a few kilometers per second is expected to facilitate the translation of the kinematics of
The Epoch of Reionization
The Universe’s dark ages end with the formation of the first generation of galaxies. These objects start emitting ultraviolet radiation that carves out ionized regions around them. After a sufficient
The effect of the intergalactic environment on the observability of Lyα emitters during reionization
Observations of high-redshift Lya sources are a major tool for studying the high-redshift universe and are one of the most promising ways to constrain the later stages of reionization. The
The Extreme Outer Regions of Disk Galaxies. I. Chemical Abundances of H II Regions
We present the first results of an ongoing project to investigate the present-day chemical abundances of the extreme outer parts of galactic disks, as probed by the emission-line spectra of a new
On the Spatial and Kinematic Distributions of Mg II Absorbing Gas in z ~ 0.7 Galaxies
We present HIRES/Keck spectra having resolution ~6 km s−1 of Mg II λ2796 absorption profiles that arise in the gas believed to be associated with 15 identified galaxies over the redshift range (0.5 ≤
150 keV Emission from PKS 2149–306 with BeppoSAX
A BeppoSAX observation of the z = 2.34 quasar PKS 2149-306 produced a strong signal in the high-energy PDS instrument up to a maximum observed energy of nearly 50 keV, 150 keV in the quasar frame.
Measuring the quasar luminosity function below the detection threshold
FACULTY NATURAL SCIENCE Department of Physics and Astronomy


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