Speaker
Description
X-ray lasers such as XFEL produce dense plasmas with out-of-equilibrium electron populations during interaction with matter. Once the pulse is over, the system returns to equilibrium in a few tens of fs, but the emission of radiation during the interaction can reveal features of the non-equilibrium electronic population during the interaction. We present numerical simulation results of the interaction of an X-ray laser with matter where the differences in time-integrated emission between a thermal and a non-equilibrium distribution are observed. For these simulations, we use a code that calculates the rate equations for atomic populations as well as the time evolution of the free electron population calculated with the Fokker-Planck equation. The results show a significant difference between the radiation emission assuming a Maxwellian and a non-equilibrium distribution, in energy bands on both sides of the laser frequency. We study these results for different materials as well as the possibility of measuring non-thermal effects.
