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Determination of V_us: recent progresses from theory

Vittorio Lubicz
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Abstract

Recent experimental and theoretical results on kaon semileptonic decays have significantly improved the determination of the CKM matrix element V_us. After briefly summarizing the impact of the new experimental determinations, I will concentrate in this talk on the theoretical progresses, coming in particular from lattice QCD calculations. These results lead to the estimate |V_us|=0.2250 +- 0.0021, in good agreement with the expectation based on the determination of |V_ud| and the unitarity of the CKM matrix.

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Vittorio Lubicz. 2005-05-26. Determination of V_us: recent progresses from theory. https://arxiv.org/abs/hep-ph/0505223

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