Advertisement

Radio Recombination Lines at Millimeter Wavelengths in HII Regions

  • M. A. Gordon
Part of the Astrophysics and Space Science Library book series (ASSL, volume 163)

Abstract

Radio recombination lines from HII regions involve much smaller principal quantum numbers at millimeter than at centimeter wavelengths. In this regime pressure broadening and partial maser effects are small and can usually be neglected. Free of these complications, millimeter-wave lines have been used to determine the electron temperatures of HII regions and to explore the atomic population processes for principal quantum numbers between 25 and 50. In general, observations appear to fit the transfer theory suggested by Goldberg (1966) with typical departure coefficients such as those calculated by Salem and Brocklehurst (1979).

This review is intended to cover the salient features of radio recombination lines (RRLs) at millimeter wavelengths but excludes discussion of the mm-wave maser lines from the star MWC349, which is described in a separate article in this volume.

Keywords

Electron Temperature Oscillator Strength Line Intensity Principal Quantum Number Departure Coefficient 
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.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Beigman, I. L., Gaisinskiy, I. M., Smitnov, G. T., Sorochenko, R. L. 1980, Preprint No. 141, Lebedev Physical Institute, Moscow.Google Scholar
  2. Burgess, A., and Summers, H. P. 1976, M. N. R. A. S., 174, 345.ADSGoogle Scholar
  3. Goldberg, L. 1969, Ap. J., 144, 1225.ADSCrossRefGoogle Scholar
  4. Gordon, M. A. 1989, Ap. J., 337, 782.ADSCrossRefGoogle Scholar
  5. Gordon, M. A., and Walmsley, C. M., 1990, submitted to Ap. J..Google Scholar
  6. Goldwire, H. C., Jr. 1969, Ap. J. Suppl., 17, 445.ADSCrossRefGoogle Scholar
  7. Griem, H. 1967, Ap. J., 148, 547.ADSCrossRefGoogle Scholar
  8. Hoang-Binh, D. 1983, Astr. Ap., 121, L19.ADSGoogle Scholar
  9. Hoang-Binh, D., Encrenaz, P., and Linke, R. A. 1985, Astr. Ap., 146, L19.ADSGoogle Scholar
  10. Kurucz, R. L. 1979, Ap. J. Suppl., 40, 1.ADSCrossRefGoogle Scholar
  11. Lilley, A. E., and Palmer, P., 1968, Ap. J. Supply., 16, 144, and a subsequent privately circulated extension.ADSGoogle Scholar
  12. Lockman, F. J., and Brown, R. L. 1975, Ap. J., 201, 134.ADSCrossRefGoogle Scholar
  13. Menzel, D. H. 1970, Ap. J. Suppl., 18, 221.ADSCrossRefGoogle Scholar
  14. Mihalas, D. 1972, Non-LTE model Atmospheres for B and О stars, NCAR- TN/STR-76 (Boulder: NCAR).Google Scholar
  15. Mihalas, D. 1989, Private communication to the author.Google Scholar
  16. Peimbert, M., Ukita, N., Hasegawa, T., and Jugaku, J. 1988, Publ. Astron. Soc. Japan, 40, 581.ADSGoogle Scholar
  17. Salem, M., and Brocklehurst, M. 1979, Ap. J. Suppl., 39, 633.ADSCrossRefGoogle Scholar
  18. Seaton, M. J. 1980, in Radio Recombination Lines, P. A. Shaver, Ed., (Dordrecht: Reidel), pp3-22.Google Scholar
  19. Shaver, P. A. 1980, Astr. Ap., 90, 34.ADSGoogle Scholar
  20. Simpson, J. A. 1973, P. A. S. P, 85, 479.ADSCrossRefGoogle Scholar
  21. Sorochenko, R. L., Puzanov, V. A., Salomonvich, A. E., and Shteinshleger, V. B. 1969, Ap. Lett., 3, 7.ADSGoogle Scholar
  22. Sorochenko, R. L., and Berulis, J. J. 1969, Ap. Lett, 4, 173.ADSGoogle Scholar
  23. Sorochenko, R. L., Rydbeck, G., and Smirnov, G. T. 1988, Astr. Ap., 198, 233.ADSGoogle Scholar
  24. Walmsley, C. M. 1989, Private communication to the author.Google Scholar
  25. Walmsley, C. M. 1990, Astr. and Ap. Suppl., in press.Google Scholar
  26. Waltman, W. B., Waltman, E. B., Schwartz, P. R., Johnston, K. J., and Wilson, W. J. 1973, Ap. J. (Letters), 185, L135.ADSCrossRefGoogle Scholar

Copyright information

© Kluwer Academic Publishers 1990

Authors and Affiliations

  • M. A. Gordon
    • 1
  1. 1.National Radio Astronomy ObservatoryTucsonUSA

Personalised recommendations