THE LAW OF MASS CONSERVATION IN THE METHOD OF POSITRON EMISSION TOMOGRAPHY

Abstract

This presentation is devoted to an actual problem of Medical Physics, which is related to the law of mass conservation in the modern diagnostic method of positron emission tomography (PET). The theoretical basis of the PET method is based on the phenomenon of annihilation of an electron and a positron with the formation of two gamma quanta, i.e. photons of short-wave electromagnetic radiation in the gamma range. The problem is that an electron and a positron have a non-zero total rest mass, while a photon is an elementary particle that has no mass. Therefore, a natural question arises, whether there is really a violation of the law of mass conservation in the process of electron and positron annihilation in one of the main diagnostic methods of PET, which is widely used in medical practice along with such diagnostic methods as magnetic resonance imaging (MRI) and computed tomography (CT)? The theoretical research conducted below provides a consistent and scientifically based answer to this fundamental question.

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