Small-angle measurements of proton-carbon nuclear reaction for secondary dose estimation

Aiming at better accuracy of secondary dose estimation in particle radiotherapy, we measured energy-angle double-differential cross sections of ion production reactions at small angles with a 40-MeV proton beam. The target used was natural abundant carbon, and it was placed in a special vacuum chamber, which allowed small angle measurements. Obtained data were compared with data measured previously and theoretical calculations based on the exciton model. It is the first time to determine the data of ion productions at angles smaller than 15°.