Comparison of experimental and simulated Kalpha yield for 400 nm ultrashort pulse laser irradiation

Ti Kalpha emission yields from foils irradiated with approximately 45 fs, p-polarized pulses of a frequency-doubled Ti:sapphire laser are presented. A simple model invoking vacuum heating to predict absorption and hot electron temperature was coupled with the cross section for K -shell ionization of Ti and the Bethe-Bloch stopping power equation for electrons. The peak predicted Kalpha emission was in generally good agreement with experiment. This contrasts strongly with previous work at the fundamental frequency. Similar predictions using particle-in-cell (PIC) code simulation to estimate the number and temperature of hot electrons also gave good agreement for yield.