Design of a ridge filter for spread-out Bragg-peak production in a pulsed 100-MeV proton beam

Abstract

We designed a ridge-filter-type modulator suitable for 100-MeV pulsed proton beam modulation. It can be applied to a variety of experiments, such as in medical technology and space technology proton beam modulation from the surface to an 8-cm depth. We also designed a 2-cm spread-out Bragg peak for cancer research using a small experimental animal orthotopic tumor model. The minimum thickness of the range modulator is specified as 2 mm for the mechanical support, and the maximum thickness in the 8-cm and 2-cm SOBP are specified as 40 mm and 12 mm, respectively. The ridge interval and the drift distance are 8 mm and 30 cm, respectively. The design was carried out using the Stopping and Range of Ions in Matter and the Monte Carlo N-particle Extended codes. The results show that the two-dimensional dose distributions of the two range modulators are uniform.