Energy straggling of he ions in Al, Cu and Au from 0.25 to 0.75 MeV/amu

Straggling of He ions has been measured in thin films of aluminium, copper and gold by the backscattering technique at energies varying from 0.25 to 0.75 MeV/a.m.u. The results are compared with the predictions of the theories of Bohr, Bethe-Livingston and Lindhard-Scharff. There is a fair agreement with the Bethe-Livingston calculations.