[en] The first measurements of the induced proton polarization Pn for the 12C(e,e',p) reaction are reported. The experiment was performed at quasifree kinematics for energy and momentum transfer (w,q) = (294 MeV, 765 MeV/c) and sampled a missing 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 1 p3/2 shell. The data for the continuum suggest that both the 1s1/2 shell and underlying l > 1 configurations contribute

[en] Recoil proton polarization observables were measured for both the p(e,e'p) and d(e,e'p)n reactions at two values of Q2 using a newly commissioned proton focal plane polarimeter at the MIT-Bates Linear Accelerator Center. The hydrogen and deuterium spin-depended observables Dll and Dl, the induced polarization Pn, and the form factor ratio Gpe/Gpm 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)

[en] The Qweak experiment at Jefferson Lab aims to make a 4% measurement of the parity-violating asymmetry in elastic scattering at very low Q² of a longitudinally polarized electron beam on a proton target. The experiment will measure the weak charge of the proton, and thus the weak mixing angle at low energy scale, providing a precision test of the Standard Model. Since the value of the weak mixing angle is approximately 1/4, the weak charge of the proton Q_w^p = 1-4 sin² θ_w is suppressed in the Standard Model, making it especially sensitive to the value of the mixing angle and also to possible new physics. The experiment is approved to run at JLab, and the construction plan calls for the hardware to be ready to install in Hall C in 2007. The theoretical context of the experiment and the status of its design are discussed

[en] We present a measurement of the induced proton polarization P_n in π⁰ electroproduction on the proton around the Δ resonance. The measurement was made at a central invariant mass and a squared four-momentum transfer of W = 1231 MeV and Q² = 0.126 GeV²/c², respectively. We measured a large induced polarization, P_n = -0.397 ± 0.055 ± 0.009. The data suggest that the scalar background is larger than expected from a recent effective Hamiltonian model

[en] The Jefferson Laboratory E93-038 collaboration conducted measurements of the ratio of the electric form factor to the magnetic form factor of the neutron, GⁿE/GⁿM, via recoil polarimetry from the quasielastic ²H((rvec e),e/(rvec n))¹H reaction at three values of Q² [viz., 0.45, 1.15, and 1.47 (GeV/c)²] in Hall C of the Thomas Jefferson National Accelerator Facility. The preliminary results for GⁿE at Q² = 0.45 and 1.15 (GeV/c)² are consistent with the Galster parameterization; however, the preliminary result for GⁿE at Q² = 1.47 (GeV/c)² lies slightly above the Galster parameterization

[en] The ratio of the electric to the magnetic form factor of the neutron, G_En/G_Mn, was measured via recoil polarimetry from the quasielastic d((pol-e),e(prime)(pol-n)p) reaction at three values of Q² [viz., 0.45, 1.15 and 1.47 (GeV/c)²] in Hall C of the Thomas Jefferson National Accelerator Facility. Preliminary data indicate that G_En follows the Galster parameterization up to Q² = 1.15 (GeV/c)² and appears to rise above the Galster parameterization at Q² = 1.47 (GeV/c)²

[en] We report values for the neutron electric to magnetic form factor ratio, G_En/G_Mn, deduced from measurements of the neutron's recoil polarization in the quasielastic ²H((rvec e), e(prime)(rvec n)) ¹H reaction, at three Q² values of 0.45, 1.13, and 1.45 (GeV/c)². The data at Q² = 1.13 and 1.45 (GeV/c)² are the first direct experimental measurements of GEn employing polarization degrees of freedom in the Q² > 1 (GeV/c)² region and stand as the most precise determinations of GEn for all values of Q²

[en] The ratio of the electric to the magnetic form factor of the neutron, g /equiv G_En/G_Mn , was measured via recoil polarimetry (R.G. Arnold, C.E. Carlson, F. Gross, Phys. Rev. C 23, 363 (1981)) from the quasielastic ²H (/mathop(e)/limitse' /mathop(n)/limits) 1H reaction at three values of Q² (viz, 0.45, 1.15, and 1.47 (GeV/c)²) in Hall C of the Thomas Jefferson National Accelerator Facility. The data reveal that GEn continues to follow the Galster parameterization up to Q² = 1.15 (GeV/c)² and rises above the Galster parameterization at Q² = 1.47 (GeV/c)²

[en] We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from ⁴He at an average scattering angle θ_lab = 5.7 degrees and a four-momentum transfer Q² = 0.091 GeV². From these data, for the first time, the strange electric form factor of the nucleon G_E^s can be isolated. The measured asymmetry of A_PV = 6.72 ± 0.84 (stat) ± 0.21 (syst) parts per million yields a value of G_E^s = -0.038 ± 0.042 (stat) ± 0.010 (syst), consistent with zero