The Range and Straggling of Protons between 35 and 120 Mev

Abstract
The range of protons in aluminum, copper, and lead has been determined with a photographic method, using the internal beam of the 95-in. synchrocyclotron of Harvard University. The method allows the simultaneous determination of the range, straggling, and the energy distribution of the protons in the internal beam. The latter was shown to have a half-width of 12 Mev. The experimental results for the range show slight, but significant deviations from tabulated values. Results for the straggling agree well with theory, if the effect of multiple scattering in the absorber is taken into account.