Non-coherent scattering in subordinate line-V. Solutions of the transfer problem

Ivan - Hubeny, P. Heinzel

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

We present several examples of the numerical solution of the radiative transfer in subordinate lines. Using a simplified physical model that yields the line source function analogous to the usual two-level-atom form modified by the presence of the redistribution function Rv in the scattering integral, we have solved the transfer problem for isothermal, plane-parallel atmospheres, both finite and semi-infinite. For finite atmospheres, we have found substantial differences between the solutions with Rv and those with complete redistribution. On the other hand, for semi-infinite atmospheres the complete redistribution appears to be a good approximation, at least for al{reversed tilde equals}au (damping parameters for the lower and upper levels, respectively). It is shown that the effect of Rv becomes more pronounced with increasing ratio au/al. Finally, it is demonstrated that an approximate form for Rv analogous to that of Kneer for RII serves as a very good approximation for computing the line profiles, particularly in the line wings.

Original languageEnglish (US)
Pages (from-to)159-168
Number of pages10
JournalJournal of Quantitative Spectroscopy and Radiative Transfer
Volume32
Issue number2
DOIs
StatePublished - 1984
Externally publishedYes

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Scattering
atmospheres
Radiative transfer
scattering
Damping
approximation
wings
Atoms
radiative transfer
damping
profiles
atoms

ASJC Scopus subject areas

  • Spectroscopy
  • Atomic and Molecular Physics, and Optics

Cite this

Non-coherent scattering in subordinate line-V. Solutions of the transfer problem. / Hubeny, Ivan -; Heinzel, P.

In: Journal of Quantitative Spectroscopy and Radiative Transfer, Vol. 32, No. 2, 1984, p. 159-168.

Research output: Contribution to journalArticle

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