Development of radiation imaging system using small-size light-weight Compton camera mounted on remotely operated machines

Miyamura, Hiroko  ; Kaburagi, Masaaki   ; Sato, Yuki  ; Kawamura, Takuma ; Idomura, Yasuhiro   ; Torii, Tatsuo  

We introduce a project that constructs the ray remote visualization system for capturing the distribution of radiation sources, which were released from the Fukushima Daiichi Nuclear Power Plant. This project executes measurements using a Compton camera mounted on a drone. The measurement datasets are reconstructed for visualizing the radiation source distribution. In this report, we investigated the accuracy of reconstruction for measurement datasets with the constraints, using a three-dimensional back-projection method and a list-mode maximum likelihood estimation method. The measurement datasets are generated by Compton camera measurement simulations for point ray sources, where the number and angle of Compton projection are limited. The reconstruction numerical experiments show that the source distribution data can be reconstructed if the number of projections is sufficiently high.