Initial-state interactions forK−-proton radiative capture

The effects of the initial state interactions on the ${\mathit{K}}^{\mathrm{-}}$-p radiative capture branching ratios are examined and found to be quite sizable. A general coupled-channel formalism for both strong and electromagnetic channels using a particle basis is presented, and applied to all the low energy ${\mathit{K}}^{\mathrm{-}}$-p data with the exception of the 1s atomic level shift. Satisfactory fits are obtained using vertex coupling constants for the electromagnetic channels that are close to their expected SU(3) values.