Improvement of spatial resolution of PIXE-CT in TIARA

TIARAにおけるPIXE-CTの空間分解能の改善

佐藤 隆博; 江夏 昌志; 横山 彰人; 神谷 富裕

Sato, Takahiro; Koka, Masashi; Yokoyama, Akihito; Kamiya, Tomihiro

To achieve higher spatial resolution of PIXE-CT, ML-EM iterative algorithm was applied to the reconstruction process. We modified the algorithm to be suited for PIXE-CT in consideration of the energy attenuation of projectiles, and measured the 3D distributions of phosphorous and lead (Pb) in a pre-fixed protest cell introduced to metal solutions containing Pb. Before micro-PIXE analysis, STIM-CT was performed, and the energy of projectiles in the sample was calculated using the Bethe-Bloch formula. After that, we obtained twenty projections of micro-PIXE, and reconstructed the 3D distributions using ten times of the iterative calculation. As a result, the 3D distributions of phosphorus and Pb in the cell were successfully obtained. Though phosphorus was entirely distributed in the cell, Pb was absorbed only on the surface. The spatial resolution estimated from the profile of Pb was less than 5 m. That is the best performance of PIXE-CT in our laboratory at this time.