Hostname: page-component-586b7cd67f-tf8b9 Total loading time: 0 Render date: 2024-11-30T12:29:27.637Z Has data issue: false hasContentIssue false
  • English
  • Français

Quasar Absorption Lines: Evolution and Clustering

Published online by Cambridge University Press:  03 August 2017

Wallace L.W. Sargent
Wallace L.W. Sargent*
Affiliation:
Palomar Observatory, 105-24, California Institute of Technology, Pasadena Ca. 91125, U.S.A.

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

A large new sample of absorption redshifts derived from the C IV doublet in the spectra of 56 QSOs has been used to study the evolution and clustering tendencies of the heavy element absorbers (thought to be galaxies). The new data have been compared with more extensive existing data for the more common Lyman α forest lines (thought to be produced by intergalactic clouds). Little or no clustering is observed in the Lyman α forest lines; moreover, there is no evidence for voids in their distribution. Clustering has been detected in the heavy element redshifts on scales Δv ≥ 200 km s−1 where relative motions of clouds within galaxies are unlikely to dominate. The degree of clustering inferred at z ≈ 2 is of the order expected on the simplest model for the evolution of galaxy clustering in cosmic time. The recent discovery of similar concentrations of absorption features extending over Δz ∼ 0.2 in the spectra of widely separated QSOs on the sky provides evidence for very large structures, probably filaments or sheets of galaxies, extending over 100 Mpc (co-moving). The Lyman α forest and heavy element redshifts evolve very differently. The Lyman lines show a rapid increase in density with increasing z, while the C IV doublets show a decrease. This result emphasizes that there are two discrete populations of absorbers. The decrease in C IV line density may be due to the effects of the onset of stellar nucleosynthesis in galaxies.

Type
Research Article
Information
Symposium - International Astronomical Union , Volume 130: Large Scale Structures of the Universe , 1988 , pp. 333 - 342
Copyright
Copyright © Reidel 1988 

References

Bahcall, J. N., and Peebles, P. J. E. 1969, Ap. J., 156, L7.Google Scholar
Bajtlik, S., Duncan, R. C., and Ostriker, J. P. 1988, Ap. J., 000, 000.Google Scholar
Barthel, P., and Tytler, D. 1987, in Absorption Lines, Proc. of a Workshop held at the Space Telescope Science Institute.Google Scholar
Bechtold, J. 1987, Ap. J., 000, 000.Google Scholar
Bergeron, J. 1987, this volume.Google Scholar
Bergeron, J. and Boissé, P. 1983, in Quasars and Gravitational Lenses, Proc. 24th Liège Symposium, p. 500.Google Scholar
Bohuski, T. J., and Weedman, D.W. 1979, Ap. J., 231, 653.Google Scholar
Boksenberg, A., and Sargent, W. L. W. 1975, Ap. J., 198, 31.Google Scholar
Carswell, R. F., Morton, D. C., Smith, M. G., Stockton, A. N., Turnshek, D. A., and Weymann, R. J., 1984, Ap. J., 278, 486.Google Scholar
Foltz, C. B., Weymann, R. J., Roser, H.-J., and Chaffee, F. H. 1984, Ap. J. (Letters), 281, L1.CrossRefGoogle Scholar
Foltz, C. B., Weymann, R. J., Peterson, B. M., Sun, L., Malkan, M. H. and Chaffee, F. H. 1986, Ap. J., 307, 504.Google Scholar
Jakobsen, P., Perryman, M. A. C., Ulrich, M. H., Machetto, F., and Di Serego Alighieri, S. 1986, Ap. J. (Letters), 303, L27.Google Scholar
Murdoch, H. S., Hunstead, R. W., Pettini, M., and Blades, J. C. 1986, Ap. J., 309, 19.CrossRefGoogle Scholar
Ostriker, J.P., and Ikeuchi, S. 1983, Ap. J. (Letters), 268, L63.Google Scholar
Peebles, P. J. E. 1973, Ap. J., 185, 413.Google Scholar
Peterson, B. A. 1978, in Proceedings of IAU Symposium 79: Largescale structure of the Universe ed. Longair, M. S. and Einasto, J. (Dordrecht: Reidel) p390.Google Scholar
Rees, M.J. and Carswell, R.F. 1987, M.N.R.A.S., 000, 000.Google Scholar
Salmon, J., and Hogan, C. 1986, M. N. R. A. S., 221, 93.CrossRefGoogle Scholar
Sargent, W. L. W. 1987, in Observational Cosmology, Proc. IAU Symposium No. 124.Google Scholar
Sargent, W. L. W. 1988 in Absorption Lines, Proc. of a Workshop held at the Space Telescope Science Institute.Google Scholar
Sargent, W. L. W., Boksenberg, A., and Steidel, C.C. 1988, Ap. J. Suppl., 00, 000.Google Scholar
Sargent, W. L. W., and Steidel, C. C. 1987, Ap. J., 322, 000.CrossRefGoogle Scholar
Sargent, W. L. W., Young, P. J., Boksenberg, A. and Tytler, D. 1980, Ap. J. Suppl., 42, 41.CrossRefGoogle Scholar
Sargent, W. L. W., Young, P J. and Schneider, D. P., 1982, Ap. J., 256, 374.CrossRefGoogle Scholar
Schechter, P. 1976, Ap. J., 203, 297.CrossRefGoogle Scholar
Shaver, P. A., and Robertson, J. G., 1983, in Proc. 24 th Liège Symposium, Quasars and Gravitational Lenses (Liège: Institut d'Astrophysique), p598.Google Scholar
Shapiro, P. 1988, this volume. Google Scholar
Shull, M. 1988, this volume. Google Scholar
Tytler, D. 1986, private communication. Google Scholar
Tytler, D. 1987a, Ap. J., 321, 49.Google Scholar
Tytler, D. 1987b, Ap. J., 321, 69.Google Scholar
Webb, J. 1988, this volume. Google Scholar
Wolfe, A. M. 1988, this volume. Google Scholar
Young, P. J., Sargent, W. L. W., and Boksenberg, A. 1982, Ap. J. Suppl., 48, 455.Google Scholar