出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：The precise measurament of the ratio RK = G(K ! en (g ))/G(K ! mn (g )) and a study of the radiative process K ! eng performed with the KLOE detector is presented, based on data collected at the Frascati e+e− collider DAFNE for an integrated luminosity of 2.2 fb−1. The ratio of G(K !en (g )) and G(K !mn (g )) decay widths has been measured for photon energies smaller than 10 MeV, without photon detection requirement, R10=(2.333±0.024stat ±0.019stat)×10−5. The systematic fractional error of 0.8%, to be compared with the statistical accuracy of 1%, is dominated by the statistics of the control-sample used (0.6% contribution) thus making possible the improvement of the results with larger data samples. The radiation-inclusive ratio RK = (2.493±0.025stat ±0.019syst)×10−5, in agreement with the Standard Model expectation. This result is used to improve constraints on parameters of theMinimal Supersymmetric Standard Model with lepton flavor violation.
