Annihilation of $\bar p+p\to e^++e^-+ \pi^0$ and $\bar p+p\to \gamma + \pi^0$ through $\omega$-meson intermediate state

TL;DR

This paper investigates proton-antiproton annihilation into a pion and a photon, analyzing the process via an omega-meson intermediate state, with calculations relevant for PANDA experiment energies.

Contribution

It introduces a detailed model of the annihilation process through omega-meson intermediates and provides cross section calculations for PANDA experiment conditions.

Findings

Cross sections are calculated for specific annihilation channels.

The model aligns well with existing scattering and annihilation data.

Results are applicable to PANDA experiment energy range.

Abstract

The s-channel annihilation of proton and antiproton into a neutral pion and a real or virtual photon followed by lepton pair emission is studied. Such mechanism is expected to play a role at moderate values of the total energy $\sqrt{s}$, when the pion is emitted around $90^{\circ}$ in the center of mass. A fair comparison with the existing data is obtained taking into account scattering and annihilation channels. The cross section is calculated and numerical results are given in the kinematical range accessible in the PANDA experiment at FAIR.