Study of the process e+e- -> omega pi0 in the phi-meson mass region with the KLOE detector

TL;DR

This study measures the e+e- -> omega pi0 cross section near the phi meson mass, extracting decay ratios and branching fractions, including the rare phi -> omega pi0 decay, using data from the KLOE detector.

Contribution

The paper provides precise measurements of omega meson decay ratios and branching fractions, and reports the first measurement of the phi -> omega pi0 decay branching ratio.

Findings

Measured the ratio Gamma(omega->pi0gamma)/Gamma(omega->pi+pi-pi0) as 0.0897 ± 0.0016

Determined BR(omega -> pi+pi-pi0) as 90.24 ± 0.19%

Derived BR(phi->omegapi0) as (4.4 ± 0.6) x 10^-5

Abstract

We have studied the e+e- -> omegapi0 cross section in the sqrt(s) interval 1000-1030 MeV using the pi+pi-pi0pi0 and pi0pi0gamma final states with a sample of ~600 pb^-1 collected with the KLOE detector at DAFNE. By fitting the observed interference pattern around M_phi for both final states, we extract the ratio of the decay widths Gamma(omega->pi0gamma)/Gamma(omega->pi+pi-pi0) = 0.0897 +- 0.0016 and derive the branching fractions BR(omega -> pi+pi-pi0)= (90.24 +- 0.19)%, BR(omega -> pi0gamma) = (8.09 +- 0.14)%. The parameters describing the e+e- -> omegapi0 reaction around M_\phi are also used to extract the branching fraction for the OZI and G-parity violating phi -> omegapi0 decay: BR(phi->omegapi0) = (4.4 +- 0.6)x10^-5.