INTERACTION OF 20-100 MeV/u HEAVY IONS WITH COLD MATTER

The stopping powers of 12 solids and 10 gases and the associated energy loss straggling have been measured at GANIL for 16-17O, 40Ar,40Ca, 84-86Kr, 100Mo and 129-132Xe ions in the energy domain 24 to 35 MeV/u. After a brief description of the experimental method, the set of data are presented and discussed. As far as stopping powers are concerned, a scaling law in Z2 relative to the 4He stopping powers at the same velocity becomes applicable when the projectile tends to be fully stripped. At the same time, the solid-gas effect, observed at low energy, vanishes. The energy loss straggling is compared to that deduced from Bohr model and some of its refinements. The theoretical value appears to be too small, by a factor 2, when the projectile is fully stripped. For partially stripped ions, the charge exchange straggling might explain the experimental observation