Comparison among alpha-particle energy losses in air obtained from data of SRIM, ICRU and experiments

In the present work, we compare the alpha-particle energy losses in air obtained from experiments and from stopping powers given in Report 49 of the International Commission of Radiation Units and Measurements (ICRU49) and Stopping and Range of Ions in Matter-2000 (SRIM-2000). The alpha energy losses have been experimentally determined for both 241Am and 230Th sources using alpha spectroscopy; such losses are observed to deviate significantly from the calculated ones. The deviations suggested that the stopping powers given by SRIM-2000 might be too high and those given by ICRU might be even higher.