Using 2.92 fb −1 of electron-positron annihilation data collected at √ s = 3.773 GeV with the BESIII detector, we obtain the first measurements of the absolute branching fractionL e + νe differential decay rate distribution, the product of the hadronic form factor and the magnitude of the CKM matrix element, f K + (0)|Vcs|, is determined 3 to be 0.728 ± 0.006(stat.) ± 0.011(sys.). Using |Vcs| from the SM constrained fit with the measured f K + (0)|Vcs|, f K + (0) = 0.748 ± 0.007(stat.) ± 0.012(sys.) is obtained, and utilizing the unquenched LQCD calculation for f K + (0), |Vcs| = 0.975 ± 0.008(stat.) ± 0.015(sys.) ± 0.025(LQCD).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.