Measurement of lineal energy distribution of heavy ion using wall-less tissue equivalent proportional counter

Tsuda, Shuichi  ; Sato, Tatsuhiko   ; Takahashi, Fumiaki  ; Satoh, Daiki   ; Sasaki, Shinichi*; Namito, Yoshihito*; Iwase, Hiroshi*; Ban, Shuichi*; Takada, Masashi*

Deposit energy distribution in microscopic site is basic information for understanding of biological effects of energetic heavy ion beams. To estimate RBE, lineal energy, y, can be an appropriate physical index. In this work, a wall-less tissue equivalent proportional counter has been designed and used for the measurement of y distributions, , for 160 MeV H, 150 MeV/u He and 490 MeV/u Si ion beams. Data of and the dose-means of , , were compared with those calculated by the microdosimetric function of PHITS. It is found that the calculated and agree fairly well with those measured, as well as the already reported result of 290 MeV/u carbon beam.