Form Factor Ratioξfrom a Measurement ofKμ3+:Ke3+Branching Ratio

Abstract

By measuring the branching ratio of $K_{\mu 3}^{}{}_{}{}^{+}$ relative to $K_{e3\mathrm{}}^{}{}_{}{}^{+}$ we have arrived at a value of $\xi \mathrm{}\left(0\right)=\frac{f_{-}\mathrm{}\left(0\right)\mathrm{}}{f_{+}\mathrm{}\left(0\right)\mathrm{}}=-0.08\mathrm{}\pm 0.15$. This is in good agreement with the Callan-Treiman relation.