Thermodynamics of ionization and dissociation in hydrogen plasmas including fluctuations and magnetic fields
Institut für Physik, Humboldt-Universität zu Berlin, Invalidenstr.
110, 10115 Berlin, Germany
Revised: 26 November 2002
Published online: 11 February 2003
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-Hückel 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.
PACS: 52.25.Kn – Thermodynamics of plasmas / 52.27.Gr – Strongly-coupled plasmas / 05.70.Ln – Nonequilibrium and irreversible thermodynamics
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2003