PLASMA ION EMISSION FROM HIGH-INTENSITY PICOSECOND LASER-PULSE INTERACTIONS WITH SOLID TARGETS

The fast ion emission from high intensity, picosecond laser plasmas ha s been measured to give the characteristic ion energy and the amount o f laser energy transferred to ions with energies greater than or equal to 100 keV/ nucleon as a function of incident intensity. The characte ristic ion energy varies from 0.2 to 1.3 MeV over the range 2.0 x 10(1 7)-2.0 x 10(18) W cm(-2). 10% of the laser energy is transferred into MeV ions at 2.0 X 10(18) W cm(-2). Calculations of stopping power in h igh density materials are presented that show that fast ions cannot be ignored in modeling fast ignitor schemes.