Measurement of the branching fraction for the decay $K_S\to \pi \mu \nu$ with the KLOE detector

Abstract

Based on a sample of 300 million $K_S$ mesons produced in $\varphi \to K_L{K}_S$ decays recorded by the KLOE experiment at the DA$\Phi$NE $e^{+}{e}^{-}$ collider we have measured the branching fraction for the decay $K_S\to \pi \mu \nu$. The $K_S$ mesons are identified by the interaction of $K_L$ mesons in the detector. The $K_S\to \pi \mu \nu$ decays are selected by a boosted decision tree built with kinematic variables and by a time-of-flight measurement. Signal efficiencies are evaluated with data control samples of $K_L\to \pi \mu \nu$ decays. A fit to the reconstructed muon mass distribution finds $7223\pm 180$ signal events. Normalising to the $K_S\to {\pi }^{+}{\pi }^{-}$ decay events the result for the branching fraction is $\mathcal{B}(K_S\to \pi \mu \nu )=(4.56\pm 0.11_{\mathrm{stat}}\pm 0.17_{\mathrm{syst}})\times 10^{-4}$.

arXiv comment16 pages, 12 figures, Accepted in PLB

References in corpus (10)

• An evaluation of |Vus| and precise tests of the Standard Model from world data on leptonic and semileptonic kaon decays
• Data handling, reconstruction, and simulation for the KLOE experiment
• Measurements of the Absolute Branching Ratios for the Dominant KL Decays, the KL Lifetime, and Vus with the KLOE Detector
• Measurements of Semileptonic KL Decay Form Factors
• Study of the branching ratio and charge asymmetry for the decay Ks->pi e nu with the KLOE detector
• Measurement of the DA$\Phi$NE luminosity with the KLOE detector using large angle Bhabha scattering
• Radiative Corrections to K^0_{l3} Decays
• Precise measurement of Gamma(Ks->pi+pi-(gamma))/Gamma(Ks->pi0pi0) with the KLOE detector at DAFNE
• Measurement of the K_L \to πμνform factor parameters with the KLOE detector
• Vus and lepton universality from kaon decays with the KLOE detector

Cited by in corpus (10)

• Beta decays as sensitive probes of lepton flavor universality
• Scrutinizing CKM unitarity with a new measurement of the $K_{\mu 3}/K_{\mu 2}$ branching fraction
• The Fermi constant from muon decay versus electroweak fits and CKM unitarity
• Update on $|V_{us}|$ and $|V_{us}/V_{ud}|$ from semileptonic kaon and pion decays
• Constraints on the $K_{\mathrm{S}}^0\to {\mu }^{+}{\mu }^{-}$ branching fraction
• Dispersive formalism for the nuclear structure correction ${\delta }_{\mathrm{NS}}$ to the $\beta$ decay rate
• Radiative corrections to semileptonic beta decays: Progress and challenges
• Theoretical point of view on Cabibbo angle anomaly
• Global Determination of $|V_{us}|$
• Search for $K_{\mathrm{S}(\mathrm{L})}^0\to {\pi }^{+}{\pi }^{-}{\mu }^{+}{\mu }^{-}$ decays at LHCb