[en] The first measurements of the differential cross section from d(γ,p)n up to 4.0 GeV were performed at the Thomas Jefferson National Accelerator Facility (TJNAF, formerly CEBAF). Bremsstrahlung photons from electron beam impinging on a copper radiator and a liquid deuterium target were employed for this experiment. The experiment was performed in Hall C where the photoprotons at forward angles in the center-of-mass were detected in the High Momentum Spectrometer (HMS) and photoprotons at backward angles were detected in the Short Orbit Spectrometer (SOS). The bremsstrahlung photon energy was reconstructed from the measured proton momentum and angle using the two-body kinematics. We report the cross section results at the proton center-of-mass angles of 37degree and 90degree. These results are in good agreement with previous lower energy measurements. The 90degree data continue to show the constituent-counting-rule behavior up to 4 GeV. The results will be compared with models based on QCD as well as those based on meson-exchange theory

[en] The first measurements of differential cross sections for deuteron photo-disintegration at photon energies up to 4 GeV were performed at the Thomas Jefferson National Accelerator Facility early in 1996. Cross section results for D(γ,p)n at proton center of mass angle of 35 deg., 53 deg. and 90 deg. will be presented. These results are in good agreement with previous measurements at low energy and extend to higher energies where data were previously unavailable. The 90 deg. degree data show behavior consistent with the constituent counting rules up to 4 GeV and are also in fair agreement with the asymptotic meson exchange model. The 37 deg. and 53 deg. data do not show clear signs of counting rule behavior, although a threshold in transverse momentum for the onset of scaling cannot be excluded