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Some recent calculations and computer programs

  • M. Salem
Part IV: Evolved H II regions and 0B-stars
Part of the Lecture Notes in Physics book series (LNP, volume 42)

Abstract

The construction of a unique spherical model with filling factor unityof a thermal radio source is briefly described. The function ω(E) must previously be obtained from radio flux observations as described by Seaton at the Symposium.Information on the availability of computer programs for determination of ω(E) and construction of the spherical model is given. Information is also given on computer programs for the computation of the hydrogen and helium line and continuum spectrum of H+ regions, and for computation of the departure coefficients from thermodynamic equilibrium, bn, at low electron temperatures.

An approximation formula for the computation of the absorption coefficient of hydrogenic ions at all electron temperatures and radio frequencies of current astrophysical interest is also given. It is expected that this formula will be of most use at electron temperatures below 1000 K, for which the standard approximation becomes inaccurate.

Keywords

Radio Frequency Electron Temperature Continuum Spectrum Spherical Model Emission Measure 
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

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Copyright information

© Springer-Verlag 1975

Authors and Affiliations

  • M. Salem
    • 1
  1. 1.Department of Physics & AstronomyUniversity College LondonLondon

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