Measurements of exclusive photoproduction processes at large values of t and u from 4 to 7.5 GeV

Abstract

Exclusive photoproduction cross sections have been measured for the processes γ p → π + n , γ p → π 0 p , γ p → π − Δ + + , γ p → ρ 0 p , γ p → K + Λ , and γ p → K + Σ 0 at large t and u values at several energies for each process between 4 and 7.5 GeV. These measurements taken together with past data taken at small values of t and u provide complete angular distributions. The data show the usual small t and u peaks and a central region in which the cross section decreases approximately as s − 7 . The results are discussed within the context of parton or constituent models.