Streater, A. | Engineering Papers

NASA NTRS1988

Transfer and redistribution of polarized light in resonance lines. I - Quantum formulation with collisions

Equations are derived quantum mechanically for the radiative transfer of polarized light and statistical equilibrium governing the formation of resonance lines in nonhydrogenic species. Redistribution due to collisions is specifically included, but magnetic fields are neglected. The formulation accounts for excited level interference and optical pumping and is applicable to solar resonance lines such as Ca II H and K and Mg II h and k.

Streater, A.↗

NASA NTRS1987

On time-dependent radiative transfer

An integral equation is developed for application to time-dependent laboratory experiments in which partial redistribution effects are important. The equation of transport with the Heasly-Kneer (1976) emission coefficient and the equation of statistical equilibrium lead to a time-dependent redistribution function containing an absorption - reemission term which decays exponentially in time and a scattering term which is instantaneous. This integral equation does not agree with an equation written by Payne et al. (1974) that has been used to compare theory with experiments. The difference between the Payne equation and the equation developed here needs to be examined in detail, since it might under some circumstances be on the same order as the difference between partial and complete redistribution.

Streater, A.↗