Branching Ratios of theK+Meson

Abstract

Stopping $K^{+}$ mesons were observed in a 12-in.-diam, 10-in.-deep xenon bubble chamber. The branching ratios of the $K_{\mu 2}$, $K_{\mu 3}$, $K_{e3\mathrm{}}$, $K_{\pi 2}$, $\tau$, and ${\tau }^{\prime }$ decay modes were calculated, giving, in percent, 63.0±0.8, 3.0±0.5, 4.7±0.3, 22.4±0.8, 5.1±0.2, and 1.8±0.2, respectively. These ratios are compared both with previous experiments and with some theoretical predictions. The ratio of the three-body pionic decay modes is consistent with the $\Delta T=\frac{1}{2}$ rule; the ratio of the three-body leptonic-decay modes is consistent with $\frac{f_{-}}{f_{+}}=0\mathrm{}$; and the $K_{\mu 2}$ branching ratio does not contradict a recent theory of universality in the two-body leptonic decays of the $\pi$ and $K$ mesons.