Accession Number : AD0722709

Title :   A Study of Equations of State/Opacity of Ionized Gases. Volume I.

Descriptive Note : Interim progress rept. 20 Oct 69-20 Sep 70,

Corporate Author : SYSTEMS SCIENCE AND SOFTWARE LA JOLLA CALIF

Personal Author(s) : Cohen,Howard D. ; Parks,Donald E. ; Petschek,Albert G.

Report Date : APR 1971

Pagination or Media Count : 125

Abstract : Developments in the calculation of the opacity and equation of state of ionized gases are described. A principal result in the CAPO code, a highly modular computer program for the calculation of thermodynamic and optical properties. Owing to its modular structure CAPO can be easily modified to allow improvements in the description of the physics. CAPO is based on the ionic model of a plasma. The system is viewed as an assemblage of ions and free electrons and each species is considered separately in the determination of the material properties. Free-free, bound-free and bound-bound processes contribute to the opacity. The line absorption is calculated in terms of a cluster or band model. Pressure ionization is treated in a manner that allows a thermodynamically consistent evaluation of thermodynamic functions. Considerations of the effect of pressure ionization on the electronic partition function suggest a reasonable method for avoiding the difficulties associated with the termination of the summation over states at quantum numbers where the binding energy is about equal to the pressure lowering of the ionization potential. (Author)

Descriptors :   (*GAS IONIZATION, EQUATIONS OF STATE), (*COMPUTER PROGRAMMING, EQUATIONS OF STATE), (*NUCLEAR EXPLOSIONS, EXPLOSION EFFECTS), THERMAL PROPERTIES, OPTICAL PROPERTIES, MEASUREMENT, PARTIAL DIFFERENTIAL EQUATIONS, INTEGRALS, STATISTICAL MECHANICS, BESSEL FUNCTIONS, DISTRIBUTION FUNCTIONS, ELECTRONS, IONS, X RAYS, SCATTERING

Subject Categories : Computer Programming and Software
      Plasma Physics and Magnetohydrodynamics
      Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE