Recoil proton polarization observables were measured for both the p( e,e ′ p ) and d( e,e ′ p )n reactions at two values of Q 2 using a newly commissioned proton Focal Plane Polarimeter at the M.I.T.-Bates Linear Accelerator Center. The hydrogen and deuterium spin-dependent observables D ℓℓ and D ℓt , the induced polarization P n and the form factor ratio G p E /G p M were measured under identical kinematics. The deuterium and hydrogen results are in good agreement with each other and with the plane-wave impulse approximation (PWIA).

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High-precision 1H(e,e'p)pi(0) measurements at Q2 = 0.126 (GeV/c)2 are reported, which allow the determination of quadrupole amplitudes in the gamma*N-->Delta transition; they simultaneously test the reliability of electroproduction models. The derived quadrupole-to-dipole ( I = 3/2) amplitude ratios, R(SM) = (-6.5+/-0.2(stat+sys)+/-2.5(mod))% and R(EM) = (-2.1+/-0.2(stat+sys)+/-2.0(mod))%, are dominated by model error. Previous R(SM) and R(EM) results should be reconsidered after the model uncertainties associated with the method of their extraction are taken into account.

The first measurements of the induced proton polarization, Pn, for the 12 C(e, e ′ p) reaction are reported. The experiment was performed at quasifree kinematics for energy and momentum transfer (ω, q) ≈ (294 MeV, 756 MeV/c) and sampled a recoil momentum range of 0-250 MeV/c. The induced polarization arises from final-state interactions and for these kinematics is dominated by the real part of the spin-orbit optical potential. The distorted-wave impulse approximation provides good agreement with data for the 1p 3/2 shell. The data for the continuum suggest that both the 1s 1/2 shell and underlying ℓ > 1 configurations contribute.

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