Simulation study of radial dose due to the irradiation of a swift heavy ion aiming to advance the treatment planning system for heavy particle cancer therapy; The Effect of emission angles of secondary electrons

重粒子線がん治療の治療計画の高度化を目指した高速重イオンの照射による動径線量のシミュレーション研究; 二次電子の放出角度の効果

森林 健悟

Moribayashi, Kengo

Aiming to advance the treatment planning system for heavy particle cancer therapy and to study cluster DNA damage, we have been developing a simulation model for radial dose due to the irradiation of a heavy ion. Now, two types of radial dose distributions have been available in the treatment planning system for heavy particle cancer therapy. However, these distributions had been developed without the detailed examinations of physical phenomena that occur near the trajectory of an incident ion, though this region is important to estimate the cell survival. The progress of computers allows us to execute such detailed examinations through simulations and to obtain radial dose closer to reality. We compare radial dose distribution obtained from our simulations with the conventional distributions and we suggest which conventional ones should be selected according to incident ion energies. Our simulation model, which has become possible in this century, is the only way to examine physical phenomena that occurs near the trajectory of an incident ion now as far as we know.