KLOE measurement of the charged kaon absolute semileptonic BR's

Abstract

This paper is devoted to the measurement of the fully inclusive absolute branching ratios of the charged kaon semileptonic decays, $K^{\pm }\to {\pi }^0{e}^{\pm }\nu (\gamma )$ and $K^{\pm }\to {\pi }^0{\mu }^{\pm }\nu (\gamma )$. The measurements have been done using a tag technique, employing the two-body decays, $K^{\pm }\to {\mu }^{\pm }\nu$ and $K^{\pm }\to {\pi }^{\pm }{\pi }^0$, and using a sample of about 410 pb${}^{-1}$ collected during the 2001 and 2002 data taking of the KLOE experiment at Daphne, the Frascati $\varphi$-factory. The results obtained are BR(K${}_{e3}^{\pm }$) = $0.04965(38{)}_{Stat}(37{)}_{Syst}$ and BR(K${}_{\mu 3}^{\pm }$) = $0.03233(29{)}_{Stat}(26{)}_{Syst}$.

arXiv commentContributed paper to Lepton Photon 2007, Daegu, Korea, 13-18 August 2007, 5 pages, 2 figures