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The Ecology of Quasar Absorption Systems

Published online by Cambridge University Press:  25 May 2016

David Tytler
David Tytler*
Affiliation:
University of California San Diego, CASS 0111, La Jolla, CA 92093-0111, [email protected]

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Gas along the lines of sight to QSOs produces narrow absorption lines from ions of the most abundant elements: H, He, C, N, O, Si, S, Mg and Fe. Most lines have rest wavelengths of a few hundred Å but some have wavelengths λ ≥ 900 Å, sufficient that they can be redshifted into the optical. The absorbing gas is normally transparent, except for Lyman continuum absorption, and dust extinction at the highest columns, so we can see hundreds of gas clouds along a line of sight. We see more absorption from higher redshifts, because the universe was denser then and the absorbing “clouds” have roughly constant proper size.

Type
Galaxies in Formation
Information
Symposium - International Astronomical Union , Volume 171: New Light on Galaxy Evolution , 1996 , pp. 299 - 302
Copyright
Copyright © Kluwer 1996 

References

Madau, P. & Shull, J.M. 1996, ApJ, Feb 1 Google Scholar
Pei, Y.C. & Fall, S.M. 1995 ApJ Google Scholar
Pettini, M., King, D., Smith, L.J. & Hunstead, R.W. 1994 in QSO Absorption Lines ed. Meylan, G., p.71 CrossRefGoogle Scholar
Steidel, C.C. 1990 ApJS, 74, 37–91 CrossRefGoogle Scholar
Verner, D.A., Barthel, P.D. & Tytler, D. 1994, AApS, 108, 287 Google Scholar