Search For Delta-I =2 Electromagnetic Currents In Pion-Photoproduction

Differential cross sections for the reactions $\ensuremath{\gamma}p\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}p, {\ensuremath{\pi}}^{+}n$ and $\ensuremath{\gamma}n\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ensuremath{-}}p, {\ensuremath{\pi}}^{0}n$ were measured in a single experiment using tagged photons in the energy region 240-450 MeV incident on $^{1}\mathrm{H}_{2}$ and $^{2}\mathrm{H}_{2}$ targets. Results of the measurements of the ratios $\frac{{\ensuremath{\pi}}^{0}n}{{\ensuremath{\pi}}^{0}p}$ and $\frac{{\ensuremath{\pi}}^{\ensuremath{-}}p}{{\ensuremath{\pi}}^{+}n}$ are presented. The ratio of isotensor to isovector amplitude is found to be 0.00\ifmmode\pm\else\textpm\fi{}0.02.