Diploma Thesis
Strahlungstransport in bewegten, sphärisch-symmetrischen Atmosphären
(Radiative transfer in moving spherical atmospheres)
Erik Meinköhn
Abstract:
Analytical expressions for the frequency-integrated mean intensity and the total flux
are obtained for expanding and collapsing spherical gray configurations in radiative
equilibrium. Such radiation fields (and the corresponding temperature distribution)
could up to a few years ago only be obtained by means of purely numerical work.
Our formulae are based on the first two moment equations of the radiative transfer
equation and a closure relation that decomposes the radiation field into an isotropic
and an outward-peaked contribution and that assures consistency of the definitions of
the moments and the corresponding transfer equation. The expressions are exact to first
order in v/c and are therefor applicable to a wide variety of objects. The depth
dependence of the opacity may be arbitrary, but is considered in detail by a power
law and found to result in formulae that can easily be handled. The previously known
relation for static spherical media is contained as a special case.
Thesis: ps.gz file (1943917 Bytes)
only available in German
