Two-dimensional positronium lifetime imaging using certified reference materials

Abstract

Positronium (Ps) is generated before electron–positron annihilation in positron emission tomography (PET). As the Ps lifetime reflects the surrounding electron density, we aimed at its use for an innovative PET imaging. Here, as our first step, we demonstrated two-dimensional Ps lifetime imaging of certified reference materials using a pair of time-of-flight PET detectors. The imaged and calculated Ps lifetimes were very close to those of the reference materials, but the error values were larger than those of the reference materials. The results suggested that the accuracy of PET imaging with the ortho-positronium lifetime could be verified by those materials.