K+nCharge Exchange at 12GeVc

Abstract

We have measured the differential cross section for the reaction $K^{+}n\to K^{0}p$ at 12 $\frac{\mathrm{GeV}}{c}$. We find that (1) the forward amplitude is essentially real, (2) the differential cross section equals that for the reaction $K^{-}p\to K^{0}n$, and (3) the differential cross section agrees well with the predictions of the Regge-pole model of Rarita and Schwarzschild. We have also compiled data on the cross section for the $K^{+}n$ charge-exchange reaction as a function of incident momentum, and compared it with that for $K^{+}p\to K^0{\Delta }^{++}$. We find that beyond threshold effects these two reactions have the same cross section.