Polarization effects in the decay of orthopositronium to three photons

Abstract

We give results for the order-$\ensuremath{\alpha}$ radiative corrections to several polarization-related effects involving the decay of ortho-positronium (o-Ps) to three photons. Specifically, we consider the decays of spin-polarized o-Ps from states of specified spin component $m$ into final states where the direction of the normal to the decay plane is measured, the linear polarization of one photon is observed, and the two variables giving the energies, or equivalently the relative orientations of the photons in the decay plane, are measured.