[16p-D311-1~11] 2.1 Detection Devices

[16p-D311-11] Measurement of linear energy deposition distribution of clinical carbon beam therapy field by thin SiC membrane detector

〇(M1)Takumi Matsumoto¹, Yudai Arai^1,2, Kei Kubodera¹, Kohei Yamaguchi¹, Ryo Yokota¹, Takeshi Ohshima², Takahiro Makino², Makoto Sakai³, Akihiko Matsumura³, Norihiro Hoshino⁴, Hidekazu Tsuchida⁴, Wataru Kada¹ (1.Gunma Univ., 2.QST, 3.GHMC, 4.CRIEPI)

Keywords:SiC, particle therapy, linear energy transfer

Linear energy transfer (LET) plays an important role in cancer treatment by heavy ion therapy, and there are considerations of maximizing treatment effect by utilizing different ion species with different LETs. This would increase the demand for advanced dosimetry techniques with a sensitivity in radiation quality, that cannot be discriminated by existing ionization chambers. In our previous study, we proposed a dosimeter using 4H-SiC Schottky Barrier Diodes (SBDs), which have excellent radiation tolerance. We successfully demonstrated LET measurement by SiC SBD and estimated Relative Biological Effectiveness (RBE) distribution in the clinical carbon therapy field. In this study, we have realized a SiC SBD with a thin membrane structure to determine fine detector volume to enable the measurement of more precise LET distributions. Here we report the results of the measurement of line energy transfer (LET) distribution using the developed thin membrane SiC SBD in an actual carbon beam cancer treatment field.