A Planned Jefferson Lab Experiment on Spin-Flavor Decomposition

Experiment E04-113 at Jefferson Lab Hall C plans to measure the beam-target double-spin asymmetries in semi-inclusive deep-inelastic $\vec p(e, e^\prime h)X$ and $\vec d(e, e^\prime h)X$ reactions ($h=\pi^+, \pi^-, K^+$ or$K^-$) with a 6 GeV polarized electron beam and longitudinally polarized NH$_3$ and LiD targets. The high statistic data will allow a spin-flavor decomposition in the region of $x=0.12 \sim 0.41$ at $Q^2=1.21\sim 3.14$ GeV$^2$. Especially, leading-order and next-to-leading order spin-flavor decomposition of $\Delta u_v$, $\Delta d_v$ and $\Delta \bar{u} - \Delta \bar{d}$ will be extracted based on the measurement of the combined asymmetries $A_{1N}^{\pi^+ - \pi^-}$. The possible flavor asymmetry of the polarized sea will be addressed in this experiment.Comment: 4 pages, 2 figures, contribution paper to SPIN2004 conferenc

Pion photoproduction in the (3,3) resonance region

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Physics, 1980.MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE.Vita.Bibliography: leaves 211-214.by Peter Eric Bosted.Ph.D

Ratio of Electron Scattering from Nuclei to Deuterium at low x and low Momentum Transfer

We have extracted ratios of cross sections for scattering electrons from high mass targets compared to low mass targets in the region of x ~ 0.02 and Q^2 < 1 (GeV/c)^2 from SLAC experiments performed over the past three decades. Additional analysis was needed for radiative corrections, target end caps and calibration runs. We observe no significant difference in the nuclear ratio for low Q^2 compared to results at Q^2 > 1.Comment: 11 pages, 8 figures, 3 table

Measurements of the Nucleon Form-Factors at Large Momentum Transfers

New measurements of the electric GE(Q2) and magnetic GM(Q2) form factors of the nucleons are reported. The proton data cover the Q2 range from 1.75 to 8.83 (GeV/c)2 and the neutron data from 1.75 to 4.00 (GeV/c)2, more than doubling the range of previous data. Scaled by the dipole fit, GD(Q2), the results forGMp(Q2) /¿pGD(Q2) decrease smoothly from 1.05 to 0.92, while GEp(Q2)/GD(Q2)is consistent with unity. The preliminary results for GMn(Q2) /¿nGD(Q2) are consistent with unity, while GEn is consistent with zero at all values of Q2