The branching ratio $$\omega \rightarrow \pi ^+\pi ^-$$ ω → π + π - revisited

Upper limit on the η → π + π − branching ratio with the KLOE detector . The KLOE Collaboration

We have searched with the KLOE detector for the P and CP violating decay η → ππ in a sample of 1.55 × 10 η’s from the decay φ → ηγ of φ-mesons produced in ee annihilations at DAΦNE. No signal is found. We obtain the upper limit BR(η → ππ)< 1.3×10 at 90% confidence level.

Measurement of the absolute branching ratio of the K + → π + π − π + ( γ ) decay with the KLOE detector

The absolute branching ratio of theK → πππ(γ) decay, inclusive of final-state radiation, has been measured using ∼17 million tagged K mesons collected with the KLOE detector at DAΦNE, the Frascati φ-factory. The result is: BR(K → πππ(γ)) = 0.05565 ± 0.00031stat ± 0.00025syst a factor ≃ 5 more precise with respect to the previous result. This work completes the program of precision measurements ...

Measurement of the branching ratio for the decay K ± → π ± π 0 π 0 with the KLOE detector

A new measurement of the absolute branching ratio BR(K → πππ) with the KLOE detector at the DAΦNE ee collider is presented, based on a sample of ∼ 3.3× 10 charged kaons tagged events, produced in the reaction ee → φ → KK. The value BR(K → πππ) = (1.781± 0.013stat ± 0.016syst)% has been obtained. The study of the non leptonic three pions decays of K has been subject of a new both theoretical and...

Measurement of the Dalitz-decay branching ratio of the π

The ratio B = Γ (π → eeγ)/Γ (π → γγ) is measured by comparing the production rates of the π in the two decay channels. The analysis is based on approximately four million hadronic decays of the Z boson recorded by the ALEPH detector in the years 1991 to 1995. The value of B is determined to be (1.140 ± 0.041)%. A recalculation of the Particle Data Group world average gives rise to a slightly im...

New measurement of the K + → π + νν̄ 1 branching ratio