Multi-fragmentation of C_(60) induced by ~4He~(2+) impact (E < 60 keV/amu) and investigated by a multi-correlation technique

摘要

In this communication, the C_(60) multi-fragmentation induced by ~4He~(2+) ion impact in the 20-240 keV energy range, is investigated. Using a multi-stop time-of-flight technique, it becomes possible to measure partial spectra corresponding to the simultaneous emission of 2-5 light charged fragments; small charged fragments are found to be accompanied by the emission of at least another one. The fragment size distribution depends on the collisional energy and the multiplicity of emitted charged fragments. It is more peaked on small sizes when the collision velocity or the multiplicity increases. Corresponding relative cross sections are also measured; processes with emission of 2 and 3 charged fragments are always dominant but their relative weights decrease slowly when the collision energy increases.