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Author Hubeny, I. ♦ Lites, B. W.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword PHYSICS ♦ HYDROGEN ♦ PHOTON-ATOM COLLISIONS ♦ SOLAR ATMOSPHERE ♦ RADIANT HEAT TRANSFER ♦ LYMAN LINES ♦ SUN ♦ CHROMOSPHERE ♦ ANALYTICAL SOLUTION ♦ GROUND STATES ♦ MULTILEVEL ANALYSIS ♦ NON-LTE ♦ LINE FORMATION
Abstract We present a robust method for solution of multilevel non-LTE line transfer problems including the effects of partial frequency redistribution (PRD). This method allows the self-consistent solution for redistribution of scattered line photons simultaneously in multiple transitions of a model atom, including the effects of resonant Raman scattering ({open_quote}{open_quote}cross-redistribution{close_quote}{close_quote}) among lines sharing common upper levels. The method is incorporated into the framework of the widely used non-LTE complete redistribution code MULTI. We have applied this method to the problem of transfer in hydrogen lines in a plane-parallel solar model atmosphere, including cross-redistribution between the H{alpha} and L{beta}, using general redistribution functions for the L{alpha} and L{beta} lines which are not restricted by the impact approximation. The convergence properties of this method are demonstrated to be comparable to that of the equivalent complete redistribution problem. In this solar model, PRD in the L{alpha} line produces the dominant influence on the level populations. It changes considerably the populations of the excited states of hydrogen, as well as the proton number density, in the middle and upper chromosphere, owing to modification of the L{alpha} wing radiation. The population of the hydrogen ground state undergoes only modest changes, however. The influence of cross-redistribution and PRD in L{beta} has a much smaller influence on the level populations but a considerable influence on the wing intensity of the L{beta} line. {copyright} {ital 1995 The American Astronomical Society.}
ISSN 0004637X
Educational Use Research
Learning Resource Type Article
Publisher Date 1995-12-01
Publisher Place United States
Journal Astrophysical Journal
Volume Number 455
Issue Number 1


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