The Study Of Quasistatic Magnetic And Electric Fields Generation And Relativistic Electron Acceleration In Intense Laser Plasma Interaction

Intense laser plasma interaction is the focus of the fast ignition scheme for inertial confinement fusion (ICF). One of its key physical problems is the generation of quasistatic magnetic (QSM) and electric (QSE) fields and the acceleration and collimation of relativistic electrons in such quasistatic fields during intense laser plasma interaction. The study of this problem is also of great significance in the discovery of the laser-particle accelerator and in the analysis of some astrophysical phenomena, such as high-energy particle acceleration and 7-burst. So far, whether from the kinetic scheme or from the fluid scheme, no self-consistent model has been presented, which can unitedly give the complete QSM (including the axial and azimuthal parts) and QSE fields. At present, the attention of electron acceleration is mainly paid to the wakefield acceleration after the very short (fs) laser pulse, where the pulse duration T_l is comparable to the characteristic time of plasma electron response ω_pe^-1 (ω_pe is the plasma electron Langmuir frequency). But in fast ignition scheme, the laser pulse duration is of ps-time-scale, usually satisfying T_l>> ω_pe^-1, thus the electron is mainly accelerated by the quasistatic fields combined with laser fields within the laser pulse, where the wakefield effects can be ignored. So far, no self-consistent work exists, which has unitedly taken the complete quasistatic fields into account and analyzed their effects in electron acceleration.From the relativistic kinetic theory (Vlasov-Maxwell equations) and the relativistic fluid theory (ten-moment Grad system of hydrodynamic equations combined with Maxwell equations), the present dissertation has respectively set up a self-consistent microcosmic kinetic model and a self-consistent fluid model for the generation of spontaneous QSM and QSE fields in intense laser plasma interaction. Both models have given the complete QSM and QSE fields from their respective theory, and moreover the results of such two models are basically consistent. The complete QSM field includes the axial component along the laser propagation direction and the azimuthal one perpendicular to the laser propagation direction. Results show that the circularly polarized (CP) laser generates both the axial magnetic field B_z and the azimuthal one B_θ. B_z is generated by the low-frequency rotational current of electron nonlinear motions in CP laser field. It comes from two respects, one is the result of the nonlinear beat of CP elec-...