A Study of \bar{p}p -> Two Neutral Pseudoscalar Mesons at the chi_c0(1^3P_0) Formation Energy

TL;DR

This paper reports on Fermilab experiment E835's study of antiproton-proton annihilation into neutral meson pairs near the chi_c0 resonance, analyzing interference effects and setting limits on certain decay channels.

Contribution

It introduces a method for extracting resonance parameters amidst dominant continuum production in antiproton-proton annihilation experiments.

Findings

Interference observed in pi0 pi0 and eta eta channels.

Measured product of branching fractions for certain channels.

Limits set on resonant production in pi0 eta and pi0 eta' channels.

Abstract

Fermilab experiment E835 has studied reactions \bar{p}p -> pi0 pi0, pi0 eta, eta eta, pi0 eta' and eta eta' in the energy region of the chi_c0(1^3P_0) from 3340 MeV to 3470 MeV. Interference between resonant and continuum production is observed in the pi0 pi0 and eta eta channels, and the product of the input and output branching fractions is measured. Limits on resonant production are set for the pi0 eta and pi0 eta' channels. An indication of interference is observed in the eta eta' channel. The technique for extracting resonance parameters in an environment dominated by continuum production is described.