Accession Number : AD0659948

Title :   SCREENED COULOMB FORMULATION OF THE IONIZATION EQUILIBRIUM EQUATION OF STATE,

Corporate Author : NAVAL RESEARCH LAB WASHINGTON D C

Personal Author(s) : Rouse,Carl A.

Report Date : 18 SEP 1967

Pagination or Media Count : 22

Abstract : The ionization equilibrium equation of state (IEEOS) is formulated relative to the numerical solutions of the Schrodinger equation with the complete screened Coulomb potential (CSCP). A finite electronic partition function and the change in ionization potential with screening radius--the radius of the mean atomic volume--which have been derived elsewhere, are used in the author's modification of the Saha equation. The resulting IEEOS is used for hydrogen and iron, where pressures at high densities and temperature are compared with pressures from the equation of state based upon the Thomas-Fermi-Dirac (TFD) statistical model of the atom. The present formulation is completely independent of TFD results; yet it gives very good agreement, for monatomic elements of all Z, with TFD pressures at high densities and temperatures, where the TFD results are believed to be reasonable; at low temperatures and densities, where the TFD pressures are either much too high or negative, the IEEOS yields the correct monatomic limit. Furthermore, in the region with T approximately equal to 1 eV and rho approximately equal to rho sub zero, the normal solid-liquid density, the IEEOS pressures are in good agreement with experimental extrapolations. Consequently, since mixtures of monatomic elements can also be handled with equal ease, the present IEEOS represents a significant improvement over the TFD equation of state. (Author)

Descriptors :   (*IONIZATION, EQUATIONS OF STATE), (*QUANTUM THEORY, ASTROPHYSICS), HYDROGEN, IRON, STATISTICAL MECHANICS, IONIZATION POTENTIALS, POTENTIAL THEORY, NUCLEAR MODELS, EQUILIBRIUM(PHYSIOLOGY), CHROMOSPHERE, STARS, MATHEMATICAL ANALYSIS, SUN

Subject Categories : Astrophysics
      Physical Chemistry
      Nuclear Physics & Elementary Particle Physics
      Quantum Theory and Relativity

Distribution Statement : APPROVED FOR PUBLIC RELEASE