Measurement of the Differential Cross Section for the reaction 2H(γ,p)n at High Photon Energies and θc.m.=90°

We have measured the differential cross section for two-body deuteron photodisintegration at θc.m.=90° and for photon energies between 0.8 and 1.6 GeV. At energies above ≃ 1.2 GeV, the data appear to obey a simple scaling law predicted by constituent-counting rules assuming parton degrees of freedom for the deuteron and nucleons. Agreement with model calculations based on meson exchange or "reduced nuclear amplitudes" is discussed.