Low-EnergyK−−αElastic Scattering

The differential cross section for $K^{-}-\alpha$ elastic scattering for $K^{-}$ laboratory momenta in the interval 110-160 MeV/c has been measured in a helium bubble chamber. The data, together with measurements of the total absorption cross section in the same region, have been fitted with a partial-wave analysis involving $s$- and $p$-wave scattering with complex phase shifts. These parameters are used for predicting the expected results of a $K$-mesonic x-ray experiment, viz., that >98% of the $K^{-}$ capture is from the $2P$ state.