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We report results from an experiment measuring the semiinclusive reaction 2 H(e, e p s ) in which the proton p s is moving at a large angle relative to the momentum transfer. If we assume that the proton was a spectator to the reaction taking place on the neutron in deuterium, the initial state of that neutron can be inferred. This method, known as spectator tagging, can be used to study electron scattering from high-momentum (off-shell) neutrons in deuterium. The data were taken with a 5.765 GeV electron beam on a deuterium target in Jefferson Laboratory's Hall B, using the CEBAF large acceptance spectrometer. A reduced cross section was extracted for different values of final state missing mass W * , backward proton momentum p s , and momentum transfer Q 2 . The data are compared to a simple plane wave impulse approximation (PWIA) spectator model. A strong enhancement in the data observed at transverse kinematics is not reproduced by the PWIA model. This enhancement can likely be associated with the contribution of final state interactions (FSI) that were not incorporated into the model. Within the framework of the simple spectator model, a "bound neutron structure function" F eff 2n was extracted as a function of W * and the scaling variable x * at extreme backward kinematics, where the effects of FSI appear to be smaller. For p s > 0.4 GeV/c, where the neutron is far off-shell, the model overestimates the value of F eff 2n in the region of x * between 0.25 and 0.6. A dependence of the bound neutron structure function on the neutron's "off-shell-ness" is one possible effect that can cause the observed deviation.

We present new experimental results for the 3 He spin structure function g 2 in the resonance region at Q 2 values between 1.2 and 3.0 (GeV/c) 2 . Spin dependent moments of the neutron were extracted. Our main result, the inelastic contribution to the neutron d 2 matrix element, was found to be small at Q 2 = 2.4 (GeV/c) 2 and in agreement with the lattice QCD calculation. The Burkhardt-Cottingham sum rule for 3 He and the neutron was tested with the measured data and using the Wandzura-Wilczek relation for the low x unmeasured region.

The differential cross section, d sigma/dt, for rho(0) meson photoproduction on the proton above the resonance region was measured up to a momentum transfer -t = 5 GeV2 using the CLAS detector at the Thomas Jefferson National Accelerator Facility. The rho(0) channel was extracted from the measured two charged-pion cross sections by fitting the pi(+)pi(-) and p pi(+) invariant masses. The low momentum transfer region shows the typical diffractive pattern expected from Reggeon exchange. The flatter behavior at large -t cannot be explained solely in terms of QCD-inspired two-gluon exchange models. The data indicate that other processes, like quark interchange, are important to fully describe rho photoproduction.