Study of the process e+e- -> omega p0 with the KLOE detector

TL;DR

This study measures omega meson decay ratios and branching fractions using e+e- collision data from the KLOE detector, providing insights into meson decay processes and violations of certain symmetries.

Contribution

The paper provides new measurements of omega decay branching ratios and the phi to omega pi0 decay branching fraction using interference patterns in e+e- collision data.

Findings

Measured ratio Gamma(omega -> pi0 gamma)/Gamma(omega -> pi+ pi- pi0) = 0.0934 +- 0.0022

Derived BR(omega -> pi+pi-pi0)= (89.94 +- 0.23)%

Calculated BR(phi -> omega pi0) = (5.63 +- 0.70) x 10^-5

Abstract

Using ~600 pb-1 collected with the KLOE detector at DAPhiNE, we have studied the production cross section of pi+ pi- pi0 pi0 and p0p0 gamma final states in e+e- collisions at center of mass energies between 1000 and 1030 MeV. By fitting the observed interference pattern around Mphi for both final states, we extract a measurement (preliminary) for the ratio Gamma(omega -> pi0 gamma)/Gamma(omega -> pi+ pi- pi0) = 0.0934 +- 0.0022. Since these two final states represent the 98% of the omega decay channels, we use unitarity to derive BR(omega -> pi+pi-pi0)= (89.94 +- 0.23)% and BR(omega -> pi0 gamma) = (8.40 +- 0.19)%. Moreover, the parameters describing the e+e- -> pi+ pi- pi0 pi0 reaction around Mphi are used to extract the branching fraction for the OZI and G-parity violating phi -> omega pi0 decay: BR(phi -> omega pi0) = (5.63 +- 0.70) x 10^-5.