Energy loss of 100 keV protons in single collisions with argon atoms

We have measured energy loss spectra of 100 keV protons interacting with argon atoms in small angle scattering under single collision conditions. The high overall energy resolution and the geometry of our setup allow a reliable determination of the mean energy loss and straggling. We have measured these quantities in dependence on the angle of scattering and find good agreement with recent calculations by Kabachnik et al. (orig.)