Measurement of $\Gamma(K(S) \to \pi^+ \pi^- (\gamma)) / \Gamma(K(S) \to \pi^0 \pi^0)$

We have measured the ratio R S π = Γ ( K S → π + π − ( γ ))/ Γ ( K S → π 0 π 0 ) with the KLOE detector at the DA Φ NE e + e − collider. This measurement is fully inclusive with respect to the π + π − γ final state. The sample of over 10 6 two-pion decays of tagged K S mesons allows a statistical error as low as ∼0.1% to be obtained. The accuracy is limited by systematic uncertainties, which are estimated primarily from data. We find R S π =2.236±0.003 stat ±0.015 syst .

Note:

9 pages, 2 Encapsulated Postscript figures. Submitted to Phys. Lett. B

electron positron: colliding beams
electron positron: annihilation
Phi(1020): electroproduction
Phi(1020): hadronic decay
K0(S): hadronic decay
K0(S): branching ratio
photon: radiation
KLOE
experimental results
Frascati Stor

References(9)

Figures(2)

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