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Thermodynamics of ionization and dissociation in hydrogen plasmas including fluctuations and magnetic fields

Werner Ebeling·Hendrik Hache·Michael Spahn
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Abstract

Applying Gibb's geometrical methods to the thermodynamics of H-plasmas we explore the landscape of the free energy as a function of the degrees of ionization and dissociation. Several approximations for the free energy are discussed. We show that in the region of partial ionization/dissociation the quantum Debye-Hueckel approximation (QDHA) yields a rather good but still simple representation which allows to include magnetic field and fluctuation effects. By using relations of Onsager-Landau-type the probability of fluctuations and ionization/dissociation processes are described. We show that the degrees of ionization/dissociation are probabilistic quantities which are subject to a relatively large dispersion. Magnetic field effects are studied.

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Werner Ebeling, Hendrik Hache, Michael Spahn. 2002-12-03. Thermodynamics of ionization and dissociation in hydrogen plasmas including fluctuations and magnetic fields. https://doi.org/10.1140/epjd%2Fe2003-00041-9

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