Measurement of the Decay Parameters of theΛ0Particle

The decay parameters of ${\Lambda }^0\to {\pi }^{-}+p$ have been measured by observing the polarization of the decay protons by scattering in a carbon-plate spark chamber. The experimental procedure is discussed in some detail. A total of 1156 decays with useful proton scatters was obtained. The results are expressed in terms of polarization parameters, $\alpha$, $\beta$, and $\gamma$ given below: