T. Ditmire et al., STRONG X-RAY-EMISSION FROM HIGH-TEMPERATURE PLASMAS PRODUCED BY INTENSE IRRADIATION OF CLUSTERS, Physical review letters, 75(17), 1995, pp. 3122-3125
The interaction of an intense laser pulse with large (similar to 100 A
ngstrom) clusters present in pulsed gas jets is shown to produce novel
plasmas with electron temperatures far in excess of that predicted by
above-threshold ionization theory. The enhanced absorption of the las
er light by the dense clusters results in the production of high ion c
harge states via collisional ionization resulting in strong x-ray emis
sion from the hot plasma.