Two-Photon Total Annihilation of Molecular Positronium

TL;DR

This paper reports the quantum electrodynamics calculated rate of the complete two-photon annihilation of molecular positronium, providing a key decay channel in the decay chart of Ps₂.

Contribution

It presents the first detailed calculation of the two-photon annihilation rate for molecular positronium using quantum electrodynamics.

Findings

Decay rate for Ps₂ two-photon annihilation: 9.0 × 10^{-12} s^{-1}

Completes the decay chart for molecular positronium

Provides theoretical foundation for experimental detection

Abstract

The rate for complete two-photon annihilation of molecular positronium Ps$_{2}$ is reported. This decay channel involves a four-body collision among the fermions forming Ps$_{2}$, and two photons of 1.022 MeV, each, as the final state. The quantum electrodynamics result for the rate of this process is found to be $\Gamma_{Ps_{2} \rightarrow \gamma\gamma}$ = 9.0 $\times 10^{-12}$ s$^{-1}$. This decay channel completes the most comprehensive decay chart for Ps$_{2}$ up to date.