Triple channel analysis of Gafchromic EBT3 irradiated with clinical carbon-ion beams

Self-developing radiochromic film is widely used in radiotherapy QA procedures. To compensate for typical inhomogeneities, the triple channel analysis method commonly photon-irradiated film. We investigated applicability of this GafchromicTMEBT3 (Ashland) irradiated with a clinically carbon-ion beam. Calibration curves were taken from EBT3 specimens monoenergetic beams different doses. Measurements lateral field shape and homogeneity performed middle passively modulated spread-out Bragg peak compared to simultaneous characterization by means 2D ionization chamber array. Additional measurements investigate quality assurance (QA) measurement performed. The triple-channel reduced relative standard deviation doses uniform carbon ion 30% (from 1.9% 1.3%) maximum almost factor 3 28.6% 9.8%), demonstrating elimination artifacts. corrected signal showed considerably improved image quantitative agreement data, thus providing clear rationale usage carbon-beam QA.