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In this paper we describe experiments conducted with high-power lasers that are attempting to replicate, for a very short time and in miniature, conditions found in the Sun. Experiments to date have reached conditions in the outer part of the Sun. To reach the Sun's centre requires compression of material to very much greater than solid density and heating to over ten million degrees. To achieve this, a new class of experiments and a new generation of high-power lasers are required. [ABSTRACT FROM AUTHOR]

Reports on the use of the configuration-interaction method to determine inner-shell photoexcitation of transitions. Interpretation of high-resolution x-ray spectroscopic observations; Assessment of the accuracy of the derived atomic data; Determination of the wave functions of the ions.

Discusses a study which examined fast heating of ultrahigh density plasma as a step toward laser fusion ignition. How the propagation of relavistic electrons in solid is measured; Details on the experiments conducted on plasma at the University of Osaka in Japan; Process used in investigating the heating efficiency.

Investigates radiation transfer through plasmas with large velocity gradients. Modeling of observed line profiles using a one-dimensional Lagrangian hydrocode, incorporating average-atom nonlocal thermodynamic equilibrium atomic physics; Dependence of values of electron and ion densities on time and space.

Large-angle Coulomb collisions allow for the exchange of a significant proportion of the energy of a particle in a single collision, but are not included in models of plasmas based on fluids, the Vlasov–Fokker–Planck equation, or currently available plasma Monte Carlo techniques. Their unique effects include the creation of fast ‘knock-on’ ions, which may be more likely to undergo certain reactions, and distortions to ion distribution functions relative to what is predicted by small-angle collision only theories. We present a computational method which uses Monte Carlo techniques to include the effects of large-angle Coulomb collisions in plasmas and which self-consistently evolves distribution functions according to the creation of knock-on ions of any generation. The method is used to demonstrate ion distribution function distortions in an inertial confinement fusion (ICF) relevant scenario of the slowing of fusion products. [ABSTRACT FROM AUTHOR]

Abstract: A procedure for performing Monte Carlo calculations of plasmas with an arbitrary level of degeneracy is outlined. It has possible applications in inertial confinement fusion and astrophysics. Degenerate particles are initialised according to the Fermi–Dirac distribution function, and scattering is via a Pauli blocked binary collision approximation. The algorithm is tested against degenerate electron–ion equilibration, and the degenerate resistivity transport coefficient from unmagnetised first order transport theory. The code is applied to the cold fuel shell and alpha particle equilibration problem of inertial confinement fusion. [Copyright &y& Elsevier]

• The ratio of an optically thick to an optically thin line can be used to measure the oscillator strength of the optically thin transition in cylindrical plasmas. • We have obtained the first experimental results of this method for the intercombination line of the He α complex at the OMEGA 60 laser. • The results agree with those from the NIST database, showing the potential of this method to measure transition strengths. We present results of measurements of the oscillator strength of intercombination lines of He-like Vanadium ions in high energy density (HED) laser-produced-plasmas and compare them with the simulations from commonly used codes and data from the NIST database. Whilst not yet sufficiently accurate to constrain different trusted atomic-physics models for the particular system studied, our results are in agreement with the available data within experimental error bars, yet differ from cruder approximations of the oscillator strength used in certain atomic-kinetics packages, suggesting that this general method could be further extended to be used as a measurement of the oscillator strength of additional atomic transitions under the extreme conditions that are achieved in HED experiments. [ABSTRACT FROM AUTHOR]