Speaker
Ms
Angela Romano
(University of Birmingham)
Description
The ratio of charged kaon leptonic decay rates BR(K --> e nu)/BR(K -->mu nu) is suppressed and predicted to excellent precision within the Standard Model. A precision test of lepton flavour universality by measurement of this ratio at the NA62 experiment at CERN, based on a dedicated sample collected in 2007, is reported. A record accuracy of 0.5% has been achieved. This result constrains the parameter space of new physics models with extended Higgs sector (including supersymmetry).