Measurement of Γ(η→ π⁺π^-γ)/Γ(η→ π⁺π^-π⁰) with KLOE experiment

2011/07/28 by F. Ambrosino, The KLOE Collaboration, Ambrosino, F. +183
Computer Science · Physics and Astronomy · #Computational Physics and Python Applications #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ex

paper · pdf · doi:10.48550/arxiv.1107.5733

arxiv created 2011/07/28 · openalex publication_date 2011/07/28 · arxiv updated 2012/08/27 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28

Abstract

We report the measurement of the ratio Γ(η→ π⁺π^-γ)/Γ(η→ π⁺π^-π⁰) analyzing a large sample of ϕ→ ηγ decays recorded with the KLOE experiment at the DAΦNE e⁺ e^- collider, corresponding to an integrated luminosity of 558 pb^-1. The η→ π⁺π^-γ process is supposed to proceed both via a resonant contribution, mediated by the ρ meson, and a non resonant direct term, connected to the box anomaly. The presence of the direct term affects the partial width value. Our result R_η=Γ(η→ π⁺ π^- γ)/Γ(η→ π⁺ π^- π⁰)= 0.1838± 0.0005_stat ± 0.0030_syst is in agreement with a recent CLEO measurement, which differs by more 3 σ from the average of previous results.

Related

• Measurement of η→π⁰γγ branching fraction with the KLOE detector
• γγ physics with the KLOE experiment
• eta Physics and phi Radiative Decays at Kloe
• Measurement of the absolute branching ratio of the K⁺ → π⁺π^-π⁺(γ) decay with the KLOE detector
• Determination of the η→π⁺π^-π⁰ Dalitz Plot slopes and asymmetries with the KLOE detector