Hostname: page-component-7479d7b7d-pfhbr Total loading time: 0 Render date: 2024-07-12T04:32:43.001Z Has data issue: false hasContentIssue false
  • English
  • Français

The ultraviolet background (intergalactic gas, the Galaxy, and subcosmic rays)

Published online by Cambridge University Press:  14 August 2015

V. G. Kurt  and
R. A. Sunyaev
V. G. Kurt
Affiliation:
Academy of Sciences, U.S.S.R. and Sternberg Astronomical Institute
R. A. Sunyaev
Affiliation:
Academy of Sciences, U.S.S.R. and Sternberg Astronomical Institute

Abstract

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.

  1. (1) Observations. – A survey is made of observations of the background radiation at UV wavelengths from above the atmosphere. Sources of the background radiation and ways of determining the extragalactic component of the background are discussed. Future observations are also discussed.

  2. (2) Cosmology. – Limits to the properties of the intergalactic gas follow from observations of the UV background. The problem of detecting galaxies at early stages in their evolution is considered.

  3. (3) The Galaxy. – Observations and theoretical estimates are given for the integrated brightness of the Galaxy at UV wavelengths beyond the Lyman-α line. Also discussed are the nature of the Lyman-α emission from the Milky Way and the principal ways of constructing the luminosity function of stars in the Galaxy from observations of the integrated UV spectrum.

  4. (4) Subcosmic Rays in the Interstellar Medium. – Fast neutral excited hydrogen atoms can be formed from charge-exchange interactions between subcosmic-ray protons and neutral interstellar gas. Upper limits are given to the energy density of subcosmic rays having E ~ 100 keV.

  5. (5) Limits on the Background Radiation in the range <912 Å. – The distribution of neutral hydrogen in the peripheries of galaxies allows limits to be obtained for the flux of metagalactic ionising radiation. The heating and ionisation of the interstellar medium by X-rays is considered.

Type
Part III: Interstellar Absorption and Emission
Information
Symposium - International Astronomical Union , Volume 36: Ultraviolet Stellar Spectra and Related Ground-Based Observations , 1970 , pp. 341 - 348
Copyright
Copyright © Reidel 1970 

References

Bowyer, C. S., Field, G. B., and Mack, J. E.: 1968, Nature 217, 32.CrossRefGoogle Scholar
Gunn, J. E. and Peterson, B. A.: 1965, Astrophys. J. 142, 1633.CrossRefGoogle Scholar
Henry, R. C., Fritz, G., Meekins, J. E., Friedman, H., and Byram, E. T.: 1968, Astrophys. J. 153, L11.CrossRefGoogle Scholar
Kurt, V. G. and Dostovalov, S. B.: 1968, Nature 217, 219.Google Scholar
Kurt, V. G. and Sunyaev, R. A.: 1967a, JETP Letters 5, 299.Google Scholar
Kurt, V. G. and Sunyaev, R. A.: 1967b, Cosmic Research [Kosmicheskie issledovanija] 5, 496.Google Scholar
Kurt, V. G. and Sunyaev, R. A.: 1967c, Astron. J. USSR 44, 1157.Google Scholar
Kurt, V. G. and Sunyaev, R. A.: 1968, JETP Letters 7, 215.Google Scholar
Lillie, C. F.: 1969, Bull. Am. Astron. Soc. 1, 132.Google Scholar
Partridge, R. B. and Peebles, P. J. E.: 1967, Astrophys. J. 177, 868.CrossRefGoogle Scholar
Pikel'ner, S.B.: 1967, Astron. J. USSR 44, 1915.Google Scholar
Roach, F. F. and Smith, L. L.: 1968, Geophys. J. 15, 227.CrossRefGoogle Scholar
Sunyaev, R. A.: 1969a, Astrophys. Letters 3, 33.Google Scholar
Sunyaev, R. A.: 1969b, Astron. J. USSR 46, 929.Google Scholar