Duality in Pion Electroproduction (E00-108) … Duality in Pion Electroproduction (E00-108) …..Why does factorization appear to work well at low energies? s ~ (Deuterium data) PRL 98, 022001 (2007) open (solid): with (without) diffractive r D region Should not depend on x But should depend on z Dashed lines: simple Parton Model prescription assuming factorization Resonances cancel (in SU(6)) in D-/D+ ratio extracted from deuterium data

LO and NLO Pdf expectations How Can We Verify Factorization? (E00-108) Neglect sea quarks and assume no pt dependence to parton distribution functions Fragmentation function dependence drops out in Leading Order open (solid): with (without) diffractive r No noticable pT-dependence in ratios x = 0.32 z = 0.55 LO and NLO Pdf expectations [sp(p+) + sp(p-)]/[sd(p+) + sd(p-)] [sp(p+) - sp(p-)]/[sd(p+) - sd(p-)]

Pion Transparency - Q2 Dependence (E01-107) Inner error bar are statistical uncertainties outer error bar are the quadrature sum of statistical and pt. to pt. systematic uncertainties. With CT No CT CT + SRC No CT + SRC ( Larson, Miller and Strikman, PRC 74, 018201 (2006) ( Cosyn, Martinez, Ryckebusch and Overmeire., PRC 74, 062201R (2006)

Pion Transparency - A Dependence (E01-107) Usually s (A) = s0 Aa T = Aa-1 a Fit of T(A) = Aa-1 at fixed Q2 ( Larson, Miller and Strikman, PRC 74, 018201 (2006) ( Cosyn, Ryckebusch et al., PRC 74, 062201R (2006)

Scaling test in Pion Electroproduction (E01-107) Hall C data at 6 GeV: 3 different experiments One of the most stringent tests of factorization is the Q2 dependence of the π electroproduction cross section, σL scales to leading order as Q-6 The Q-6 QCD scaling law is consistent with the JLab σL data Limited Q2 coverage and large uncertainties Q2=1.4-2.2 GeV2 Q2=2.7-3.9 GeV2 σL σT

Precise Measurement of the EMC Effect in Light Nuclei (E03-103) Goals: Measure EMC Effect for: 3He - unmeasured at x > 0.4 4He - improve existing data by factor of ~2 Investigate “scaling” of the EMC Effect at large x, but W < 2 GeV Compare “exact” calculations of light nuclei to data to improve our understanding of the contribution of conventional nuclear physics effects to the mass dependence of F2 3He Preliminary Results Analysis of 3He and 4He nearly complete; heavy target analysis still in progress (A. Daniel, Houston thesis ) 3He ratio has significant correction due to “proton excess” Shape independent of A, especially at large x(ξ)

G0 N-Delta Parity Violation (E04-104) Elastic Region: G0 Inelastic Region: N D Measurement: Parity-violating asymmetry of electrons scattered inelastically ANΔ gives direct access to GANΔ Directly measure the axial (intrinsic spin) response during N →Δ+ transition Will find GANΔ over a range of Q2 0.05 GeV/c2 < Q2 < 0.5 GeV/c2. First measurement in neutral current process Data: Inelastic electrons measured by G0 Scattered from both LH2 and LD2, each at two energies (362MeV & 687MeV) IN Status: Data taking: Completed March ‘07 First stage of corrections (backgrounds, detector efficiencies, etc): In progress Determination of Q2: Coming soon Asymmetry (ppm) vs Octant (LH2 @ 687MeV) OUT Asymmetry (ppm) BLINDED Octant Raw Asymmetry (averaged over inelastic region)

F2/R on Deuterium and nuclear targets ( E04-001 / E06-009) Online cross sections! Deuterium Precision L/T separated structure functions F1, F2, FL, R H, D, Al, C, Fe/Cu Low Q2 ran January 2005 Moment extractions (compare to lattice predictions at Q2 = 4 GeV2) Useful for neutrino MC input Carbon