Evidence for double diffraction in $\mathrm{pp}$ interactions at 300 GeV/c

We have observed evidence for the double diffraction process $\mathrm{pp}\to N^{*}{N}^{*}$ at 300 GeV/c. The symbol $N^{*}$ is used here to refer to the low-mass enhancement which decays into three charged particles (with or without neutrals). The cross section for this reaction is measured to be 0.12±0.05 mb. The cross section for the single-beam-diffraction reaction, $\mathrm{pp}\to p{N}^{*}$, is measured to be 0.82±0.08 mb. These data are in good agreement with the predictions of the factorization hypothesis.