Triggered-bubble-chamber study of the reactionπ+p→Δ++π0π0at 16 GeV/c

Abstract

The SLAC 40-inch bubble chamber augmented by an array of lead-glass detectors was used to study the reaction ${\pi }^{+}$p→${\Delta }^{++}$ ${\pi }^0$ ${\pi }^0$ at 15.7 GeV/c. No new high-mass neutral mesons are seen at a sensitivity of 14.2 events/μb. A moments and amplitude analysis indicates that only S and D waves contribute to the ${\pi }^{+}$ ${\pi }^{\mathrm{-}}$→${\pi }^0$ ${\pi }^0$ cross section. A one-pion-exchange-model calculation is performed using phase-shift measurements from other experiments. The older phase shifts from Estabrooks and Martin are in better agreement with our data than are the more recent ones of Biswas et al.