Ionization equilibrium in dense plasmas

Thesis/Dissertation · Thu Jan 01 04:00:00 EST 1987

OSTI ID:6058826

Ying, R

The average degree of ionization for a strongly coupled plasma is investigated and calculated. Two widely used approaches: the Saha equation method and the Thomas-Fermi (TF) statistical atomic model are adopted to determine the degree of ionization. Both methods are modified in a number of ways to include the strong-coupling effect in the plasma. In the Saha equation approach, the strong-coupling effects are introduced through: (i) a replacement of the Coulomb potential by a screened Debye potential; (ii) adoption of the Planck-Larkin partition function; (iii) description of the electron component by Fermi-Dirac statistics. The calculated degree of ionization exceeds that obtained from the original Saha equation, exhibits a minimum as a function of the density and shows an abrupt phase transition from weakly ionized to a fully ionized state. The zero-temperature TF model for compressed ions and the finite-temperature TF model for ions are investigated for the first time. In order to take into account the strong-coupling effect in a systematic way, a strong-coupling TF model is set up. Favorable results with the relatively simple approximations indicate that the newly established strong-coupling TF model is a more systematic and physically consistent approach.

• Research Organization: Boston Univ., MA (USA)
• OSTI ID: 6058826
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700103* -- Fusion Energy-- Plasma Research-- Kinetics
ATOMIC MODELS
DEBYE LENGTH
DIMENSIONS
EQUATIONS
EQUILIBRIUM
IONIZATION
LENGTH
MATHEMATICAL MODELS
PARTICLE MODELS
PLASMA
PLASMA DENSITY
SAHA EQUATION
STRONG-COUPLING MODEL
THOMAS-FERMI MODEL