2023/09/26 by Matteo Orfano, Orfano, Matteo, Fiammetta Pagano +21 · 1 citation
Medicine · Physics and Astronomy · #Atomic and Subatomic Physics Research #FOS: Physical sciences #Instrumentation and Detectors (physics.ins-det) #Materials Science (cond-mat.mtrl-sci) #Medical Imaging Techniques and Applications #Radiation Detection and Scintillator Technologies
paper · pdf · doi:10.48550/arxiv.2309.14968
openalex publication_date 2023/09/26 · openalex created_date 2023/09/29 · openalex updated_date 2026/07/28
Time-of-Flight Positron Emission Tomography is a medical imaging technique, based on the detection of two back-to-back γ-photons generated from radiotracers injected in the body. Its limit is the ability of employed scintillation detectors to discriminate in time the arrival of γ-pairs, i.e. the coincidence time resolution (CTR). A CTR < 50 ps that would enable fast imaging with ultralow radiotracer dose. Monolithic materials do not have simultaneously the required high light output and fast emission characteristics, thus the concept of scintillating heterostructure is proposed, where the device is made of a dense scintillator coupled to a fast-emitting light material. Here we present a composite polymeric scintillator, whose density has been increased upon addition of hafnium oxide nanoparticles. This enhanced by +300% its scintillation yield, surpassing commercial plastic scintillators. The nanocomposite is coupled to bismuth germanate oxide (BGO) realizing a multilayer scintillator. We observed the energy sharing between its components, which activate the nanocomposite fast emission enabling a net CTR improvement of 25% with respect to monolithic BGO. These results demonstrate that a controlled loading with dense nanomaterials is an excellent strategy to enhance the performance of polymeric scintillators for their use in advanced radiation detection and imaging technologies.