Photoproduction of Charged Pion Pairs on Protons

A high-statistics (100 000 events) measurement of photoproduction of charged pion pairs on protons is reported in two parts. First, the measured cross sections are presented in a three-dimensional data matrix where all the dynamical features are explicitly shown. Second, fitting the data in the energy region 2.6-6.8 GeV with various assumptions on $\rho$ production indicates that ${\frac{d\sigma }{\mathrm{dt}}|}_{t=0\mathrm{}}$ for the photoproduction of $\rho$ decreases with increasing energy similar to $\pi N$ scattering.