Shift of K-lines in Laser Produced Dense Plasmas

In order to develop X-ray probes for Compton scattering on warm dense plasmas K-lines have been investigated by irradiation of solid targets with intense ultra-short pulsed lasers, e. g. spectroscopy of chlorine Kα (2p→ 1s) and Kβ (3p→ 1s) was performed at Europa Laser Facility LLNL. Measurements of the characteristic X-ray emission show that average line positions shift as function of laser energy: At low irradiation a red shift to lower energies is observed. Increasing the laser energy the line is blue shifted back to higher energies [1, 2, 3].