Simulations of electron-beam scattering by spontaneous magnetic fields in a laser plasma

The feasibility of experimental investigation of spontaneous magnetic fields in a laser plasma with the help of a fast-electron beam is discussed. A three-dimensional program was written to calculate the kinetics of these electrons in sign-variable magnetic fields and calculations were made for different plasma parameters. An electron energy of ~100 keV is shown to be sufficient for the investigation of magnetic fields in the plasma plume; this energy for a compressed laser target ranges between 4 and 8 MeV. Electrons with this energy can be generated employing an additional picosecond laser pulse synchronised with the main heating pulse.