[7p-PA8-1~80] 2 Ionizing Radiation（Poster）

[7p-PA8-2] A feasibility study of scintillation fiber imager for range verification of particle therapy

〇Yu Ohashi¹, Fuyuki Tokanai², Takeo Iwai³, Kouzi Morimoto⁴, Syunsuke Kurosawa^2,5 (1.Yamagata Univ. rikou, 2.Yamagata Univ. rigaku, 3.Yamagata Univ .igaku, 4.Rikagakukenkyusho, 5.Tohoku Univ)

Keywords:carbon therapy, carbon range, scintillation fiber

Radiotherapy with carbon beams will be started in 2020 at Yamagata
University Hospital. Ion beam of 12C accelerated up to 70% of speed of
light is irradiated to tumors, and most of its energy deposits at the
end of the range (Bragg peak). Thus, it is expected that a relatively
higher dose concentrated at the region of tumors without influencing
healthy tissues. In the radiotherapy with carbon beams, a real time
monitor is desired to verify the actual range of the carbon bean
within a body. We have been developing a scintillation fiber imager
(SFI) for the real-time monitor utilizing the secondary particle
ejected by the interaction between the 12C beam and materials of body.
The SFI includes two sets of a scintillation fiber layer, each layer
consists of 64 fiber with a square cross section of 0.25 mm2.
One of them gives X-directional position and other gives Y-direction
position.Four MAPMTs of Hamamatsu R5900-L16 were used to read out the
signal of SFI.Test measurement has been successfully carried out with
beta-ray source of 90Sr. The characteristics have been also
investigated by a computer simulation using the particle and heavy ion
transport code system (PHITS).