학술논문
Measurement of the branching fraction for the decay K-S -> pi mu nu with the KLOE detector
Document Type
Author
Babusci, D.; Berlowski, M.; Bloise, C.; Bossi, F.; Branchini, R.; Budano, A.; Cao, Bo; Ceradini, F.; Ciambrone, R.; Curciarello, F.; Czerwinski, E.; D'Agostini, G.; Dane, E.; De Leo, V; De Lucia, E.; De Santis, A.; De Simone, R.; Di Cicco, A.; Di Domenico, A.; Domenici, D.; D'Uffizi, A.; Fantini, A.; Fermani, R.; Fiore, S.; Gajos, A.; Gauzzi, R.; Giovannella, S.; Graziani, E.; Ivanov, V. L.; Johansson, Tord; Kang, X.; Kisielewska-Kaminska, D.; Kozyrev, E. A.; Krzemien, W.; Kupsc, Andrzej; Lukin, P. A.; Mandaglio, G.; Martini, M.; Messi, R.; Miscetti, S.; Moricciani, D.; Moskal, R.; Parzych, S.; Passeri, A.; Patera, V; del Rio, E. Perez; Santangelo, R.; Schioppa, M.; Selce, A.; Silarski, M.; Sirghi, F.; Solodov, E. P.; Tortora, L.; Venanzoni, G.; Wislicki, W.; Wolke, Magnus
Source
Physics Letters B. 804
Subject
Language
English
ISSN
0370-2693
1873-2445
1873-2445
Abstract
Based on a sample of 300 million K-S mesons produced in phi -> KLKS decays recorded by the KLOE experiment at the DA Phi NE e(+)e(-) collider we have measured the branching fraction for the decay K-S -> pi mu nu. The K-S mesons are identified by the interaction of K-L mesons in the detector. The K-S -> pi mu nu decays are selected by a boosted decision tree built with kinematic variables and by a time-of-flight measurement. Signal efficiencies are evaluated with data control samples of K-L -> pi mu nu decays. A fit to the reconstructed muon mass distribution finds 7223 +/- 180 signal events. Normalising to the K-S -> pi(+)pi(-) decay events the result for the branching fraction is B(K-S -> pi mu nu) = (4.56 +/- 0.11(stat) +/- 0.17(syst)) x 10(-4). It is the first measurement of this decay mode and the result allows an independent determination of vertical bar V-us vertical bar and a test of the lepton-flavour universality. (c) 2020 The Author. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).