Innershell ionization in xenon clusters irradiated with an intense x-ray laser pulse

The interaction of xenon clusters with an intense soft x-ray laser (λ=13.9 nm, pulse width ∼7 ps, intensity ≤2x1010 W/cm2) was examined using time of flight (TOF) mass spectrometers. The cross section for inner-shell ionization of Xe 4d electron at hv=90 eV is by ten times larger than photoionization of a valence electron. For larger clusters, the anomalous enhancement of Xe3+ ion yield to Xe2+ ion has been observed. In order to clarify the Auger decay associated with inner hole in the cluster, the electron energy distribution was measured. (author)