TY  - Data
T1  - Feasibility Study on Whether Divergent Aperture Can be Used on Proton Therapy Radiotherapy
A1  - Xiao Guoqing
DO  - 10.12072/ncdc.imp.db4138.2023
PY  - 2023
DA  - 2023-12-28
PB  - National Cryosphere Desert Data Center
AB  - In this paper, the process of proton beam passing through the beam limiting hole of divergent collimator and traditional collimator is modeled by using the Monte Carlo software Topas. The influence of the edge scattering effect of the two collimators on the dose and neutron spectrum distribution is analyzed. The proton beam at 70110, 160, 200, 230, 250 MeV energy is measured respectively, It is found that the edge scattering effect of traditional aperture is the most obvious under the proton beam of 70mev. The flatness and uniformity of the transverse dose curve at the depth of 0.5cm from the water tank surface reach 4.63% and 108.05% respectively. With the increase of depth, the edge scattering effect gradually weakens and disappears near the Bragg peak. The flatness and uniformity of the collimator are reduced to 1.28% and 101.31% respectively at 70mev after using the divergent collimator beam limiting hole. The 100, 160 and 200MeV proton beams are improved to some extent. For the proton beam with energy close to 250 MeV, the transverse dose curve of divergent collimator with beam limiting hole has no advantage. The dose difference caused by edge scattering effect decreases with the increase of water depth. For each energy proton, the secondary neutrons decrease after using the beam limiting hole of divergent collimator. The results show that the beam limiting hole of divergent collimator is effective in PSPT, which provides data support for further clinical application.
DB  - NCDC
UR  - http://www.ncdc.ac.cn/portal/metadata/934c80d7-fa32-4e1d-bd89-01a79b90203d
ER  -