講演情報
[8a-PA2-5]Development of a Three-Dimensional Position-Sensitive Detector for Integrated Scatterer–Absorber Compton Imaging
〇shuwei zhao1, Hiroyuki Takahashi1 (1.Tokyo univ.)
キーワード：
Phase shifting、Three dimensional detector
This study proposes a three-dimensional position-sensitive detector for integrated scatterer–absorber Compton imaging. Conventional Compton cameras generally consist of separated scatterer and absorber detectors, and their imaging performance is strongly affected by the spatial resolution of each detector and the geometrical separation between them. To realize a more compact imaging system, we propose a single detector module that can function as both the scatterer and the absorber.The proposed detector combines a phase-shifting readout scheme and double-sided readout. The phase-shifting structure improves the transverse spatial resolution by enabling sub-pixel sampling without increasing the number of readout channels. In addition, double-sided readout provides depth-of-interaction information from the light output ratio between the two sides, allowing three-dimensional interaction position estimation.When a gamma ray undergoes Compton scattering inside the detector and is subsequently absorbed at another position within the same detector volume, both the deposited energies and the three-dimensional interaction positions can be measured. The Compton scattering angle can then be estimated from the energy information, while the scattering direction can be determined from the reconstructed interaction positions.As a first step, a Geant4 simulation model was constructed to evaluate the feasibility of this detector concept. A gamma-ray point source was placed in front of the detector module, and the deposited energy, interaction sequence, and three-dimensional position information were recorded. The simulation was used to investigate the probability of obtaining valid Compton events and to evaluate the potential of single-module Compton imaging. The proposed detector concept is expected to contribute to compact, high-resolution gamma-ray imaging systems.