Differential Cross Section and Polarization in the Reactionπ++p→K++Σ+from 3 to 7 GeV/c

We have measured the differential cross section and polarization for the reaction ${\pi }^{+}+p\to K^{+}+{\Sigma }^{+}$ for $K$ laboratory angles between 3° and 17°. The reaction is dominated by a large forward peak which shrinks rapidly and decreases slowly in size with increasing energy. A break in this exponential occurs at $-t=0.4\mathrm{}$ ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^2$ beyond which the cross section falls much more slowly. The polarization is small for values of $-t$ less than 0.3 beyond which it becomes large and positive and remains positive to the largest angles measured. It is independent of energy within experimental errors.