Gamma-gamma Angular Correlations of Beta Minus Decays as a Novel Medical Imaging Modality

Abstract

We point out that the medical imaging by non-collinear angular correlations of gamma ray pairs subsequent to the beta minus (Β^-) emission of a radioactive isotope maybe superior to the conventional positron emission tomography (PET) for at least two reasons. Event by event determination of decay vertices of stationary heavy nuclei by non-collinear angular correlations of emitted photons enhances the image quality as no back projections are necessary and the emissions are devoid of the PET artifacts of random positron motions. The present-day PET machines can adapt the new modality with simple hardware and software modifications. We performed the measurements of the angular correlations of 617-372 keV gamma ray pair in the decay of ⁴³K (Β^-) ⁴³Ca, produced in the ⁴⁴Ca(p,2p) ⁴³K reaction at the 65 MeV proton beams of the AVF cyclotron at the Research Centre, Japan. We present the yields and gamma ray angular correlations of this pair of gamma rays.