Research on quality testing for active spot scanning proton and heavy ion accelerator

Abstract

Objective To study the quality testing of dose delivery system of the active spot scanning proton and heavy ion accelerator, in order to provide the reference for the quality control of related equipment. Methods In the four therapy rooms, both 0.6 cc chambers and Gafchromic EBT3 films were used, respectively, to test the accelerator for dose reproducibility, dose linearity, dose stability, depth dose distribution, beam scanning position deviation and radiation field uniformity in each therapy room. Results Dose reproducibility variation coefficients are all less than 1.5%, dose linearity’s maximum deviations less than 2%, dose stability’s deviations less than 2%, depth dose distribution stability within 2%, beam scanning position deviation less than 1 mm, consistency of irradiation field’s deviation less than 2 mm, and flatness within ±5%. Conclusions The indicators about quality testing for the active spot scanning proton and heavy ion accelerator are all in line with the requirements of IEC standards draft. Key words: Proton and heavy ion accelerator; Active spot scanning; Quality test