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New results from KLOE

KLOE Collaboration
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Abstract

The most precise determination of Vus comes from semileptonic kaon decays. We have measured with the KLOE detector at DAFNE, the Frascati phi-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 dominated by the theoretical error on the form factor, f+(0). A new determination of the ratio Vus/Vud is also presented, based on our precise measurement of the absolute branching ratio for the decay K -> mu nu (gamma), combined with lattice results for the ratio f_K/f_pi. New results on CPT symmetry and quantum mechanics test have also been achieved, which are based on the first measurement of the charged asymmetry for KS -> pi e nu decay and on interferometry studies using the phi -> KL KS -> pi+ pi- pi+ pi-.

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KLOE Collaboration. 2007-01-09. New results from KLOE. https://arxiv.org/abs/hep-ex/0701008

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