Resonance-Interference Method for DeterminingKΣNParity

A method is given for determining the orbital parity of the $\pi +\Sigma$ state of the 1520-Mev, strangeness (-1), resonance by measuring angular distributions and hyperon polarizations resulting from the process $K^{-}+p\to \pi +\Sigma$. The method depends on the observation of interference between the resonance state and at least one other state, and on the assumption that the relative phase of the resonant and nonresonant state increases with energy. The validity of this assumption is discussed. Since the orbital parity of the $K^{-}+p$ state may be determined by continuing the measurements from the resonance energy down to the $K^{-}+p$ threshold energy, this method may yield the intrinsic $K\Sigma N$ parity. The various ambiguities in the determination of partial wave amplitudes from experimental data are discussed. It is shown that the many-channel unitarity condition may be useful in resolving some of the ambiguities.