Numerical simulations of thermally generated currents in laser plasmas

Summary form only given. The generation of large currents and intense magnetic fields in laser-generated plasmas has attracted a great deal of attention especially at high intensities necessary for laser fusion (/spl sim/10/sup 14/ W/cm/sup 2/). The fields are generated by conversion of the thermal energy in the plasma to magnetic energy in regions where the temperature and density gradients are not parallel: i.e. near the edge of the laser beam and possibly in an expanding shock wave. We present the results of numerical simulations at lower laser intensities (/spl sim/10/sup 8/ W/cm/sup 2/) which are obtainable with modest power laboratory lasers. Currents at the multi-kiloampere level and magnetic fields at the multi-kilogauss level can be produced. The simulations were performed with the 2 1/2 dimensional magnetohydrodynamic (MHD) code MACH2. Briefly, MACH2 is a single fluid, three-temperature code which is well suited for the complex shapes that arise in real experiments. Features include a generalized ohm´s law, multi-material capability, and realistic equations of state and transport coefficients computed from the SESAME tables at Los Alamos National Laboratory.