This item is only available for download by members of the University of Illinois community. Students, faculty, and staff at the U of I may log in with your NetID and password to view the item. If you are trying to access an Illinois-restricted dissertation or thesis, you can request a copy through your library's Inter-Library Loan office or purchase a copy directly from ProQuest.
Permalink
https://hdl.handle.net/2142/20145
Description
Title
Higher-order processes in stellar opacities
Author(s)
Cundiff, Kirby Ray
Issue Date
1996
Doctoral Committee Chair(s)
Lamb, Frederick K.
Department of Study
Physics
Discipline
Physics
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
Physics, Astronomy and Astrophysics
Language
eng
Abstract
In this thesis we calculate the influence of many-body interactions on the opacity the solar core and other non-relativistic astrophysical environments. The many-body interactions are of two basic types-multi-photon and multi-particle. Multi-photon processes of the following types are calculated: two-photon bound-bound absorption, two-photon bound-bound absorption on resonance, two-photon free-free absorption, and double Compton scattering (two photons are absorbed and one is emitted). When the electrons are in free states, higher order corrections to multi-photon interactions (free-free absorption and double Compton scattering) are found to be proportional to the temperature over the plasma frequency, $T/\omega\sb{p},$ in most astrophysical environments, where the electron energy width, $\Gamma\sb{e},$ is much smaller than the temperature, T. When the electrons are bound, the relationship is somewhat more complicated. The inverse-bremsstrahlung cross-section is calculated in a plasma using the methods of finite temperature field theory to relate it to the imaginary part of the photon self-energy. The importance of multi-particle interactions is found to be determined by the electron energy width over the temperature, $\Gamma\sb{e}/T.$ Noise of the cross-section corrections that were calculated contribute an opacity correction that is larger than two percent in any of the astrophysical environments examined (the solar core, the solar interior, and white dwarf envelopes).
Use this login method if you
don't
have an
@illinois.edu
email address.
(Oops, I do have one)
IDEALS migrated to a new platform on June 23, 2022. If you created
your account prior to this date, you will have to reset your password
using the forgot-password link below.
