Development of high timing performance detector towards reconstruction-less positron emission tomography

To realize reconstruction-less positron emission tomography (PET), PET detector with coincidence time resolution (CTR) of 35 ps full width at half maximum (FWHM) is indispensable. In this study, we developed a microchannel plate photomultiplier tube (MCP-PMT) in which a Cherenkov radiator was integrated. Thanks to the integration, Cherenkov photons emitted in the radiator are smoothly propagated to the photocathode, resulting in good timing performance. Experiment for evaluating the CTR of the developed detectors were conducted. Consequently, the CTR of 41.7 ps FWHM, which corresponds to spatial resolution of 6.3 mm FWHM, was obtained. We can expect that further improvement on the CTR is achievable by optimizing the Cherenkov radiator, e.g. lead fluoride and hafnium oxide. For a future work, we will develop the Cherenkov-radiator-integrated MCP-PMT with the radiator optimization. (author)