Magnetic field-assisted wakefield generation and electron acceleration by Gaussian and super-Gaussian laser pulses in plasma

Abstract

This study focuses on electron acceleration and wakefield produced by Gaussian and Super-Gaussian (SG) laser pulses through plasma medium in the attendance of an external magnetic field. Two shapes of different laser spatial profiles Gaussian and SG are considered. Besides, governing equations for analysis of laser wakefield and electron acceleration by using of hydrodynamics fluid equations, Maxwell’s equations and perturbation technique for Gaussian and SG laser pulses in weakly nonlinear regime have been derived. In addition, influence of the external magnetic field strengths, laser intensity, the pulselength, the plasma electron density and the laser frequency on the wakefield and the electron energy gain have been investigated. Numerical results indicate that by increasing of external magnetic field, the amplitude of wakefield increases. Moreover, it is observed that wakefield amplitude excited by SG laser pulse in comparison with Gaussian laser pulse is larger when external magnetic field is increased. Furthermore, it is found that wakefield amplitude and shape of wakefield generation in within homogeneous plasma greatly are related to the laser profile type, selected laser parameters and external magnetic field. In addition, it is seen that influence of external magnetic field, while laser intensity enhances, on the electron energy gain in SG and Gaussian laser pulses is insignificant.