Refluxing of fast electrons in solid targets irradiated by intense, picosecond laser pulses

The propagation of fast electrons produced in the interaction of relativistically intense, picosecond laser pulses with solid targets is experimentally investigated using Kα emission as a diagnostic. The role of fast electron refluxing within the target, which occurs when the electrons are reflected by the sheath potentials formed at the front and rear surfaces, is elucidated. The targets consist of a Cu fluorescence layer of fixed thickness at...