Stopping power and straggling of 80-500 keV lithium ions in C, Al, Ni, Cu, Se, Ag, and Te

Stopping power and straggling of lithium ions with velocities around the Bohr velocity (E = 175 keV) have been measured for a number of self-supporting target foils (C, Al, Ni, Cu, Se, Ag, and Te). Except for carbon, the stopping powers increase considerably faster with energy than proportional to velocity. At the Bohr velocity, the measured stopping powers agree rather well with semiempirical calculations based on the Hartree-Fock-Slater wavefunctions for low Z2, while they are up to 50% higher for large Z2. It is discussed whether it is possible to obtain reliable straggling data, which are not obscured by target non-uniformity and texture effects, from the measured energy distribution widths. The most promising targets were found to be copper, silver, and selenium, but even for these targets, inhomogeneities may still cause the extracted straggling parameters to be too high. (orig.)