Stopping power and straggling of 0.2-2.0 MeV protons and 0.3-3.1 MeV 4He ions in erbium

Abstract

2014 The stopping power cross section and energy straggling of protons and 4He ions in erbium films evaporated in vacuum, were determined using a backscattering technique in the energy range from 0.2 to 2.0 MeV for protons, and 0.3 to 3.1 MeV for 4He ions. The experimental stopping power data were fitted by means of Brice’s formula, and agree with Ziegler’s semiempirical calculations. The accuracy of the measurements was estimated to be ± 3 %. The energy straggling results for protons in erbium are in agreement with the predictions of Bethe and Livingston. Disagreement between the experimental and theoretical points for energy straggling of 4He ions is explained by the influence of the thickness non uniformity in the target. J. Physique 43 (1982) 485-491 1 MARS 1982, Classification Physics Abstracts 61.80M