FRAGMENTATION OF SPUTTERED TA CLUSTER IONS OVER THE TIME RANGE OF 1 NS TO O.1 MS - LIFETIME AND INTERNAL ENERGY-DISTRIBUTIONS

Ta-n(+) clusters (n=4-8) were produced by sputtering of Xe ions with a n energy of 9 keV; the fragmentation of these cluster ions has been st udied over the time range of 1 ns to 0.1 ms. It has been established t hat the fragmentation rate dependence on time from the moment of clust er emission is a power function rather than an exponential function. T he lifetime distributions and the average lifetime <(tau)over bar> hav e been calculated for Ta-4(+) (<(tau)over bar>=1.9 ns) and Ta-5(+) (<( tau)over bar>=10.7 ns) clusters. The internal energy distributions of Ta-4(+) and Ta-5(+) have been obtained by the theory of Rice-Ramsperge r-Kassel (RRK); the interconnection between parameters of the distribu tions and the experimental conditions of sputtering is briefly discuss ed.