Large-Angle High-Energy Photoproduction of Singleπ+Mesons from Liquid Hydrogen

We have measured angular distributions for single photoproduced ${\pi }^{+}$ mesons at 4.0-, 5.0-, and 7.5-GeV incident photon energies and at lab angles from 11° to 66° with the Stanford Linear Accelerator Center 8-GeV spectrometer. Combined with previous Stanford Linear Accelerator Center results, this gives complete angular coverages for this range of energies. The data show the usual "$t$" and "$u$" diffraction peaks and a "central plateau" region dropping as $S^{-7.3\mathrm{}}$.