Ultrafast laser-based thermal X-ray sources

Abstract

The effects of hot electrons on the thermal radiative properties (brightness, duration and spectral shape) and dynamics of solid density plasmas, generated during the interaction of a femtosecond laser and a solid target, are assessed. Line and broadband thermal emissions with duration between 500 fs and 700 fs, have been successfully produced with peak power between 1 and 10 MW, when the fraction of laser energy in the hot electron population was less than 2%, and when the hot electron energy density at the target surface was less than 1 KJ / cm 2 .