A simulation study on reduction of the background component using veto counters for imaging of therapeutic proton beams by measuring secondary electron bremsstrahlung using a parallel-hole collimator

摘要

A simulation study on reduction of a background (BG) component for an imaging method of therapeutic proton beams by measuring secondary electron bremsstrahlung (SEB) component was performed using the Monte Carlo method. We simulated the images obtained by measuring the SEB and BG components using a parallel-hole-type X-ray camera placed close to an irradiation target. We found that reduction of the BG component was possible by utilizing veto counters placed close to the imaging detector of the X-ray camera. The ratio of the BG component to the sum of the SEB and BG components was able to be reduced from 73% to approximately 20%. (C) 2019 The Japan Society of Applied Physics