ReactionK+p→K+π+π−pat 2.53, 2.76, and 3.20 GeV/c

The reaction $K^{+}p\to K^{+}p{\pi }^{+}{\pi }^{-}$ is studied at incident beam momenta of 2.53, 2.76, and 3.20 GeV/c, using the Argonne 30-in. hydrogen bubble chamber. Cross sections for the production of $K^{*0\mathrm{}}\mathrm{}\left(890\right)\mathrm{}$, $N^{*++}\mathrm{}\left(1236\right)\mathrm{}$, and the double-resonance channel $K^{+}p\to K^{*0\mathrm{}}\mathrm{}\left(890\right)\mathrm{}{N}^{*++}\mathrm{}\left(1236\right)\mathrm{}$ have been determined. We compare the production and decay angular distributions for the double-resonance channel with the predictions of several models which assume pion exchange. The decay angular distributions have also been compared with quark-model predictions. We find that none of the models tested completely accounts for all the features of the data. In addition, a low-mass enhancement in the $K\pi \pi$ system at 1300±10 MeV is observed.