Measurements of the ion energies resulting from irradiation of Xe clusters
with 800 nm laser pulses in the intensity range 2 x 10(15)-5 x 10(16) Wcm(-
2) are reported. The maximum ion energies as a function of mean cluster siz
e and laser intensity were determined at a constant laser-pulse duration of
similar to 65 and 90 fs respectively-a factor of 3 shorter than previous s
caling studies. Comparisons made between experimental results and numerical
simulations of the laser-cluster interaction have shown the importance of
considering a distribution of cluster sizes. We have found the addition of
a log-normal size distribution to simulations using the nanoplasma model of
cluster excitation improves the agreement between numerical and experiment
al data.