Setsuo Ichimaru

Statistical physics of dense plasmas: Thermodynamics, transport coefficients and dynamic correlations

Abstract We review the current status of the theoretical developments in the study of the interparticle correlations in dense plasmas and the transport and elementary processes. The specific features considered are the strong Coulomb-coupling effects in the dense ion systems, the varied degrees of Fermi degeneracy in the electron systems and the mutual coupling between the ion and electron systems. The subjects covered are confined, more or less, to those areas where the authors were able to make some contributions and progress through theoretical studies since the previous review [1]. Relevant experimental works are also cited and are compared with the theoretical results.

Enhancement of thermonuclear reaction rate due to strong screening. II. Ionic mixtures

The calculation of the enhancement factor for the rate of thermonuclear reactions in the strong-screening regime is extended to the cases involving plasmas with two different ion species. The calculation is based on the recent results of Monte Carlo computations for such two-component plasmas. With appropriate definition and combination of the plasma parameters we find that the screening potentials in two-component plasmas exhibit a linear dependence at intermediate distances, quite similar to that found for one-component plasmas. Application to the calculation of carbon ignition in the carbon--oxygen core of a highly evolved star is discussed.

Collisional equipartition rate for a magnetized pure electron plasma

The collisional equipartition rate between the parallel and perpendicular velocity components is calculated for a weakly correlated electron plasma that is immersed in a uniform magnetic field. Here, parallel and perpendicular refer to the direction of the magnetic field. The rate depends on the parameter κ=(b/rc)/, where rc=(T/m)1/2/Ωc is the cyclotron radius and b=2e2/T is twice the distance of closest approach. For a strongly magnetized plasma (i.e., κ≫1), the equipartition rate is exponentially small (ν∼exp[−5(3πκ)2/5/6]). For a weakly magnetized plasma (i.e., κ≪1), the rate is the same as for an unmagnetized plasma except that rc/b replaces λD/b in the Coulomb logarithm. (It is assumed here that rc λD, the plasma is effectively unmagnetized.) This paper contains a numerical treatment that spans the intermediate regime κ∼1, and connects onto asymptotic results in the two limits κ≪1 and κ≫1. Also, an improved asymptotic expression for the rate in the high‐field limit is derived. T...

Thermodynamics and Correlational Properties of Finite-Temperature Electron Liquids in the Singwi-Tosi-Land-Sjölander Approximation

The dielectric formulation is applied to the study of the static correlations in the electron liquids at finite temperatures. The strong coupling effects arising from the exchange and Coulomb correlations are taken into account through the local-field correction in the Singwi-Tosi-Land-Sjolander approximation. The resulting integral equations are solved self-consistently, and the thermodynamic quantities are evaluated at various combinations of the plasma parameters in the range of the intermediate Fermi degeneracy. The results are parametrized in the form of the analytic formulas, which satisfy a number of exact boundary conditions and limiting behaviors.

Electrical and thermal conductivities of dense matter in the liquid metal phase. II - Low-temperature quantum corrections

On calcule les corrections des coefficients de transport de la matiere dense dues a la nature quantique des ions semiclassiques. Les resultats numeriques sont parametrises en formules analytiques

Nuclear reaction rates in dense carbon-oxygen mixtures

New, first principles calculations of nuclear reaction rates in dense carbon-oxygen mixtures appropriate to Type I supernova progenitors are presented for both fluid and bcc crystalline-solid phases, based on accurate Monte Carlo evaluations of the screening potentials and a correct treatment of the quantum-statistical effects. A blocking effect of oxygen is discovered in the pycnonuclear reaction of carbon. The results are compared with the existing theories in the limit of one-component plasma cases, both for the screening potentials and for the reaction rates. Examples of the carbon ignition curve are shown. 25 refs.

Metal-Insulator Transitions in Dense Hydrogen : Equations of State,Phase Diagrams and Interpretation of Shock-Compression Experiments

First-principles formulations of the equations of state for hydrogen in metallic and insulator phases are presented, leading to a phase diagram predicting first-order metal-insulator transitions in dense hydrogen. The theory explicitly takes into account the effects of strong electron-ion coupling near the transitions as well as those of lowering or elimination of the atomic and/or molecular levels due to plasma screening. It is shown that the results of recent shock-compression experiments prove consistent with such first-order insulator-to-metal transitions. These observations predict a discontinuous distribution of density and resistivity with a large magnetic Reynolds number near the Jovian surface; the latent heat through the metal-to-insulator transitions is estimated.

Theory of Plasma Heating by Fluctuating Electric Fields–Effects of Correlation Times

The heating rate of the particles of a given species under the influence of fluctuating electric fields in a plasma is calculated explicitly in terms of those physical parameters relevant to specification of the system: These are the average drift velocity and the velocity spread around it for the particles; the integrated strength, the peak frequency and the spectral width around it for the fluctuation spectrum. The effects arising from the correlation times of the fluctuations are elucidated through investigation of various limiting cases.

Freezing transition and phase diagram of dense carbon-oxygen mixtures in white dwarfs

An accurate calculation is presented of the the phase diagram associated with the solidification transitions in dense carbon-oxygen mixtures appropriate to the interiors of white dwarfs, resulting in a novel prediction of an azeotropic diagram. It is concluded that chemical separations would not take place thermodynamically through such solidification processes. 20 references.

Theory of anomalous resistivity and turbulent heating in plasmas

General expressions for the d.c. resistivity and the heating rates of the electrons and the ions are obtained in terms of the spectral functions of particle correlation functions; the results are rigorous and applicable to both quiescent and turbulent plasmas. The method of analysis is based on the moment calculations of the first equations of the Bogo-liubov-Born-Green-Kirkwood-Yvon hierarchy for a multicomponent plasma. Definite predictions are made on the relative magnitudes of the electron and ion heating rates when the nature of the turbulent fluctuations is known. Some of the well-known formulas for the anomalous resistivity are obtained as specific cases of the present calculation. It is shown that a consideration of the critical fluctuations alone cannot account for the anomalous resistivity in a turbulent plasma.