K+ decay in flight

From a sample of 10⁵ K⁺ decays in flight the following branching ratios were obtained: $K_{\mu 2}=\left(63.24\pm 0.44\right)$, $K_{\pi 2}=\left(21.18\pm 0.28\right)$, τ(K⁺→π⁺π⁺π⁻)=(5.56±0.20)%, τ′(K⁺→π⁺π⁰π⁰)=(1.84±0.06)%, $K_{\mu 3}\left(3.33\pm 0.16\right)$, and Kₑ₃=(4.86±0.10)%. The phase-space distributions for three-body semileptonic modes were studied in detail from a second sample of 10⁵ decays. For 4017 K⁺→π⁰e⁺ν events, λ₊=0.029±0.011. Limits on scalar and tensor form factors of $\left|\frac{f_S}{f_{+}}\right|<0.13$ and $\left|\frac{f_T}{f_{+}}\right|<0.75$ (90% confidence) were obtained. For K⁺→π⁰μ⁺ν a parametrized fit to 3900 events assuming λ₊=λ₋=+0.030 gave $\xi =-0.09\pm 0.28$.