05 10 02 8 v 1 1 0 O ct 2 00 5 KLOE extraction of Vus from kaon decays and lifetimes
نویسنده
چکیده
The most precise determinations of Vus comes from semileptonic kaon decays. The KLOE experiment at DAΦNE the Frascati φ factory , has measured all the experimental inputs to Vus for both neutral and charged kaons. Preliminary results for BR(K± → π0e±ν) and BR(K± → π0μ±ν), and for τ± are presented, together with measurements of the KLe3 and KLμ3 decay BR, the KSe3 decay BR and the KL lifetime τL. From our results for the 5 branching ratios and τL we find Vus=0.2258±0.0022. We have also measured the fully inclusive K μ2(γ) absolute branching ratio for which we obtain BR(K+ → μν(γ))=0.6366±0.0017. Combining this value with recent lattice results for fK/ fπ gives Vus=0.2223±0.0026.
منابع مشابه
Unitarity and universality with kaon physics at KLOE
All relevant inputs for the extraction of the CKMmatrix element Vus fromKL, KS and K ± decays have been measured at KLOE. From a global fit using only KLOE results, but KS lifetime, a value of |Vus|f+(0) = 0.2157 ± 0.0006 is obtained, where f+(0) is the form factor parametrizing the hadronic matrix element evaluated at zero momentum transfer. Comparison of the values of f+(0) Vus for Ke3 and Kμ...
متن کامل/ 04 02 03 0 v 1 2 0 Fe b 20 04 KLOE Results on Rare K 0 Decays
This paper describes the neutral Kaon dataset and physics measurements of KLOE at DAΦNE. A brief discussion on the prospects for detector upgrades and analysis of other K S rare decays is also included.
متن کاملKAON PHYSICS AT KLOE THE KLOE COLLABORATION a
The most precise determination of Vus comes from semileptonic kaon decays. We have measured with the KLOE detector at DAΦNE, the Frascati φ factory, all the experimental inputs to Vus for both neutral and charged kaons. Using our results we extract the value of Vus with ∼ 0.9% fractional error, which is entirely dominated by the theoretical error on the knowledge of the normalization of the dec...
متن کاملx / 05 07 08 8 v 2 1 7 O ct 2 00 5 Measurement of the K L meson lifetime with the KLOE detector
We present a measurement of the KL lifetime using the KLOE detector. From a sample of ∼ 4 × 10 KSKL pairs following the reaction ee → φ → KSKL we select ∼ 15 × 10 KL → πππ decays tagged by KS → ππ events. From a fit of the proper time distribution we find τL = (50.92 ± 0.17stat ± 0.25syst) ns. This is the most precise measurement of the KL lifetime performed to date. PACS: keywords:
متن کاملO ct 2 00 5 Measurement of the Absolute Branching Ratio for the K + → μ + ν ( γ ) Decay with the KLOE Detector
We have measured the fully inclusive K+ → μ+ν(γ) absolute branching ratio with the KLOE experiment at DAΦNE, the Frascati φ–factory. From some 865,283 K+ → μ+ν(γ) decays obtained from a sample of ∼5.2 × 108 φ-meson decays, we find BR(K+ → μνμ(γ))=0.6366±0.0009stat.±0.0015syst., corresponding to an overall fractional error of 0.27%. Using recent lattice results on the decay constants of pseudosc...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2005