Electron acceleration by laser wakefield and x-ray emission at moderate intensity and density in long plasmas

Abstract

The dynamics of electron acceleration by laser wakefield and the associated x-rays emission in long plasmas are numerically investigated for parameters close to the threshold of laser self-focusing. The plasma length is set by the use of dielectric capillary tubes that confine the gas and the laser energy. Electrons self-injection and acceleration to the 170 MeVs are obtained for densities as low as 5 x 10^18 cm^3 and a moderate input intensity (0.77 x 10^18 W/cm^2). The associated x-ray emission at the exit of the capillary tube is shown to be an accurate diagnostic of the electrons self-injection and acceleration process.