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K_(e3) decays and CKM unitarity

Cirigliano, V. and Neufeld, H. and Pichl, H. (2004) K_(e3) decays and CKM unitarity. European Physical Journal C, 35 (1). pp. 53-65. ISSN 1434-6044. doi:10.1140/epjc/s2004-01745-1.

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We present a detailed numerical study of the K_{e3} decays to O(p^6,(m_d-m_u)p^2,e^2p^2) in chiral perturbation theory with virtual photons and leptons. We describe the extraction of the CKM matrix element |V_(us)| from the experimental K_(e3) decay parameters. We propose a consistency check of the K^+_(e3) and K^0_(e3) data that is largely insensitive to the dominating theoretical uncertainties, in particular the contributions of order p^6. Our analysis is highly relevant in view of the recent high statistics measurement of the K^+_(e3) branching ratio by E865 at Brookhaven which does not indicate any significant deviation from CKM unitarity but rather a discrepancy with the present K^0_(e3) data.

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Additional Information:© Springer-Verlag / Società Italiana di Fisica 2004. Received: 22 January 2004, Published online: 30 April 2004. Work supported in part by IHP-RTN, Contract No. HPRN-CT2002-00311 (EURIDICE) and by Acciones Integradas, Project No. 19/2003 (Austria), HU2002-0044 (MCYT, Spain). We thank J. Bijnens, G. Ecker, J. Gasser and H. Leutwyler for useful remarks. We have profited from discussions with G. Isidori, B. Sciascia, T. Spadaro, and J. Thompson. V.C. is supported by a Sherman Fairchild fellowship from Caltech.
Funding AgencyGrant Number
European UnionHPRN-CT2002-00311
Acciones Integradas19/2003
Ministerio de Ciencia y Tecnologia (MCYT)HU2002-0044
Sherman Fairchild FoundationUNSPECIFIED
Issue or Number:1
Record Number:CaltechAUTHORS:20170408-160424209
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Official Citation:Cirigliano, V., Neufeld, H. & Pichl, H. Eur. Phys. J. C (2004) 35: 53. doi:10.1140/epjc/s2004-01745-1
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:76121
Deposited By: 1Science Import
Deposited On:15 Jun 2017 21:51
Last Modified:15 Nov 2021 16:57

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