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arXiv · 0804.4577

Measurement of the absolute branching ratio of the K+ -> pi+ pi0 (gamma) decay with the KLOE detector

F. Ambrosino·A. Antonelli·M. Antonelli·F. Archilli·C. Bacci·P. Beltrame·G. Bencivenni·S. Bertolucci·C. Bini·C. Bloise·S. Bocchetta·F. Bossi·P. Branchini·P. Campana·G. Capon·T. Capussela·F. Ceradini·F. Cesario·S. Chi·G. Chiefari·P. Ciambrone·F. Crucianelli·E. De Lucia·A. De Santis·P. De Simone·G. De Zorzi·A. Denig·A. Di Domenico·C. Di Donato·B. Di Micco·A. Doria·M. Dreucci·G. Felici·A. Ferrari·M. L. Ferrer·S. Fiore·C. Forti·P. Franzini·C. Gatti·P. Gauzzi·S. Giovannella·E. Gorini·E. Graziani·W. Kluge·V. Kulikov·F. Lacava·G. Lanfranchi·J. Lee-Franzini·D. Leone·M. Martemianov·M. Martini·P. Massarotti·W. Mei·S. Meola·S. Miscetti·M. Moulson·S. Müller·F. Murtas·M. Napolitano·F. Nguyen·M. Palutan·E. Pasqualucci·A. Passeri·V. Patera·F. Perfetto·M. Primavera·P. Santangelo·G. Saracino·B. Sciascia·A. Sciubba·A. Sibidanov·T. Spadaro·M. Testa·L. Tortora·P. Valente·G. Venanzoni·R. Versaci·G. Xu
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Abstract

We have measured the absolute branching ratio of the K+ -> pi+ pi0 (gamma) decay, using about 20 million tagged K+ mesons collected with the KLOE detector at DAFNE, the Frascati phi-factory. Signal counts are obtained from the fit of the distribution of the momentum of the charged decay particle in the kaon rest frame. The result, inclusive of final-state radiation, is BR(K+ -> pi+ pi0 (gamma))=0.2065+/-0.0005_{stat}+/- 0.0008_{syst}.

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F. Ambrosino, A. Antonelli, M. Antonelli, F. Archilli, C. Bacci, P. Beltrame, G. Bencivenni, S. Bertolucci, C. Bini, C. Bloise, S. Bocchetta, F. Bossi, P. Branchini, P. Campana, G. Capon, T. Capussela, F. Ceradini, F. Cesario, S. Chi, G. Chiefari, P. Ciambrone, F. Crucianelli, E. De Lucia, A. De Santis, P. De Simone, G. De Zorzi, A. Denig, A. Di Domenico, C. Di Donato, B. Di Micco, A. Doria, M. Dreucci, G. Felici, A. Ferrari, M. L. Ferrer, S. Fiore, C. Forti, P. Franzini, C. Gatti, P. Gauzzi, S. Giovannella, E. Gorini, E. Graziani, W. Kluge, V. Kulikov, F. Lacava, G. Lanfranchi, J. Lee-Franzini, D. Leone, M. Martemianov, M. Martini, P. Massarotti, W. Mei, S. Meola, S. Miscetti, M. Moulson, S. Müller, F. Murtas, M. Napolitano, F. Nguyen, M. Palutan, E. Pasqualucci, A. Passeri, V. Patera, F. Perfetto, M. Primavera, P. Santangelo, G. Saracino, B. Sciascia, A. Sciubba, A. Sibidanov, T. Spadaro, M. Testa, L. Tortora, P. Valente, G. Venanzoni, R. Versaci, G. Xu. 2008-09-16. Measurement of the absolute branching ratio of the K+ -> pi+ pi0 (gamma) decay with the KLOE detector. https://doi.org/10.1016/j.physletb.2008.07.070

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