出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：A precision measurement of the helicity-suppressed ratio RK = G(K± ! e±n )/G(K± !m±n ) has been performed using the full dedicated data sample collected by the NA62 experiment at CERN in 2007-2008. The result, RK = (2.488±0.010)×10−5, is in agreement with the Standard Model expectation and allows to test the lepton flavor universality with the same accuracy as the tau and pion leptonic decays.
