Break-up and Coherent Photoproduction of ???? Mesons on the Deuteron
We present new break-up and coherent data for ???? meson photoproduction on the deuteron, using a deuterium target and tagged bremsstrahlung photons up to 1 GeV. The differential cross sections for the coherent process were measured from threshold to 800 MeV. They are much smaller than those previously reported. The break-up channel provides a direct measurement of the neutron to proton differential cross section ratios. At the ????11(1535) resonance peak, ????????/????????=0.68±0.06 leading to an isoscalar to isovector amplitude ratio of ????????/????????=0.096±0.02.
