No abstract available

No abstract available

[en] The importance of non-Markovian contributions is due to their apparance in asymptotic particle trajectories involved in the Dupree-Weinstock and renormalized theories of plasma turbulence. Several recent misunderstanding about such terms appeal for some comments. From the Klimontovich equation, the derivation of various forms of the exact master equation is reviewed for plasma turbulence: the equivalence between the non-Markovian forms of the master equation (like the Weinstock equation) and apparently Markovian forms (like the subdynamics result) is used to study non-Markovian contributions. The latter are defined in the same way as in statistical mechanics. Contrary to what has been claimed by Jones, and Pelletier, respectively, (i) the usual quasi-linear description actually involves an additional adiabatic or Markovian approximation, and (ii) the apparently Markovian equation and the group property of the corresponding propagator are not restricted to the white noise case. It is shown that these misleading conclusions are mainly due to restricted particular understandings of the non-Markovian property. Explicit results of non-Markovian contributions are derived in the lowest order approximation. Such non-Markovian terms yield significative contributions to asymptotic perturbed trajectories involved in renormalized theories of plasma turbulence

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[en] We present a steady-state ionization model wich is convenient for laser plasmas, and simple enough to deal with short computer calculations. This model is built assuming partial L.T.E. (local thermodynamic equilibrium) over excited bound states and free states, and gathering them in one super state. Significant discrepancies with L.T.E. or C.E. are found for mean Z value, spectroscopic ratio ..., giving better agreement with experimental results. At last, possibility of extension to time dependant model is discussed

No abstract available

[en] Description of the set-ups and measurements for in-core and laboratory research of non-equilibrium nuclear-exciting plasma of various gas mixtures are demonstrated in this paper. Excitation of gas medium was produced by products of the ³ He(n,p)T, ²³⁵ U(n,f)F nuclear reactions at in-core experiments, and by products of the radioisotopes ²¹⁰ Po, ²³⁹ Pu fission at laboratory ones. The data of these investigations allows as to estimate threshold parameters of the nuclear pumped laser as to study the electron kinetics characteristics of nuclear-exciting plasma. The developed optical diagnostic methods allows to measure spectral and integral luminescence characteristics, in particular absolute population of excited states of atom and molecules and elementary processes constant rates. The probe methods of diagnostic allows to determine such plasma parameters as conductivity, concentration of charged particles and in some cases the coefficient of positive and negative ions and electron mobility and recombination coefficients. Some experimental results of the investigation are shown

[en] The determination of the ionization energy is regarded as a nonequilibrial process. The reduction of the ionization energy in a plasma is calculated by means of the statistical operator for quasi-equilibrium and produces a value of -1.5 kappae². (author)

[en] The coefficient of recombination of the first electron is taken as an example for an atomic process embedded in a nonequilibrium anisotropic neutral plasma of stripped ions and electrons. The plasma is assumed to be in a stationary state of quasi-equilibrium with each particle species having three temperatures along each direction of space. Though this is a genuine problem of kinetic plasma theory the quasi equilibrium allows to make use of generalizations of the fluctuation-dissipation-theorem (FDT), which normally is only applied in thermal equilibrium, even up to this anisotropic nonequilibrium state

[en] Letter to the editor