Energy loss straggling of swift heavy ions in metal foils at E vertical bar A similar to 2 MeV/u

Measured energy loss straggling data for partially stripped 2 MeV/u S-32, B r-79 and 1.47 MeV/u I-127 heavy ions traversing Al, Cu, Ag and Au vacuum ev aporated metal foils of various thicknesses are reported and compared with the classical theories of the collisional energy loss straggling and Yang's empirical formula. The estimated charge exchange straggling seems to domin ate the experimental straggling widths within this energy region. A simple analytical expression predicting the overall straggling at 2 MeV/u for any projectile-target system is derived. The measured straggling data for 8.78 MeV alpha particles from a ThC radioactive source are also reported: (C) 20 00 Elsevier Science B.V. All rights reserved.