Diffraction dissociation in four-prong proton-proton interactions at205 GeVc

We analyze the diffraction process in four-prong $\mathrm{pp}$ interactions at $205 \frac{\mathrm{GeV}}{c}$. The $p{\pi }^{+}{\pi }^{-}$ state contributes only 25% to the proton dissociation and, as observed for momenta below $30 \frac{\mathrm{GeV}}{c}$, this state is confined to masses ∼ 3 GeV. Substantial excitation occurs into states involving three or more pions and with masses as high as 7 GeV. Isovector-exchange background is small, as studied using the missing mass of the system recoiling from a prominent ${\Delta }^{++}$ state.