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Optical studies of galactic nebulae and of their exciting stars : The role of dust on the radius of the ionized hydrogen sphere

  • M. C. Lortet
Part III: IR-Sources, Masers and Compact H II Regions
Part of the Lecture Notes in Physics book series (LNP, volume 42)

Abstract

From new observational data, Georgelin, Lortet-Zuckermann and Monnet (1975) and Chopinet and Lortet-Zuckermann (1975) have rediscussed the use of the Zanstra method in order to derive the rate of stellar ultra-violet photons from hot stars and have studied the relation between the excitation of the nebular spectrum and the spectral type of the exciting star. I wish to show here that dust grains mixed within the ionized gas cannot be an efficient competitor with hydrogen atoms for the absorption of stellar Lyman photons, and thus that this mechanism cannot affect significantly the effective temperature scale derived by Georgelin, Lortet-Zuckermann and Monnet.

Keywords

Effective Temperature Spectral Type Excitation Parameter Ionize Hydrogen Efficient Competitor 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. Chopinet, M., and Lortet-Zuckermann, M.C. 1975, Low dispersion spectra of small H II regions and planetary nebulae (Paper VIII), submitted to Astr. and Ap.Google Scholar
  2. Conti, P.S. 1973, Ap.J., 179, 181.Google Scholar
  3. Georgelin, Y.M., Lortet-Zuckermann, M.C., and Monnet, G. 1975, The rate and fate of stellar ultraviolet photons (Paper VII), submitted to Astr. and Ap.Google Scholar
  4. Mathis, J.S. 1971, Ap.J., 167, 261.Google Scholar
  5. Mezger, P.G., Smith, L.E., and Churchwell, E. 1974, Astr. and Ap., 32, 269.Google Scholar
  6. Panagia, N. 1973, Astr. J., 78, 929.Google Scholar
  7. Panagia, N. 1974, Ap.J., 192, 221.Google Scholar
  8. Petrosian, V., Silk, J., and Field, G.B. 1972, Ap.J. (Letters), 177, L69.Google Scholar

Copyright information

© Springer-Verlag 1975

Authors and Affiliations

  • M. C. Lortet
    • 1
  1. 1.Département d'Astrophysique FondamentaleObservatoire de MeudonMeudonFrance

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