The current data for the nucleon-virtual photon longitudinal spin asymmetry A1 on the proton and neutron have shown that the ratio of the polarized-to-unpolarized down-quark parton distribution functions, Δ d/d, tends towards -1/2 at large x, in disagreement with the perturbative QCD prediction that Δ d/d approaches 1 but more in line with constituent quark models. As a part of experiment E06-014 in Hall A of Jefferson Lab, double-spin asymmetries were measured in the scattering of a longitudinally polarized electron beam of energies 4.74 and 5.89 GeV from a longitudinally and transversely polarized 3He target in the deep inelastic scattering and resonance region, allowing for the extraction of the neutron asymmetry A1n and the ratios Δ d/d and Δ u/u. We will discuss our analysis of the data and present results for A1 and g1/F1 on both 3He and the neutron, and the resulting quark ratios for the up and down quarks in the kinematic range of 0.2 2 2 for our deep inelastic scattering data. Invoking duality, we also extract A1n and g1n/F1n in the resonance region, characterized by 0.6 2 2. Our measurements are compared to the world data and various theoretical models and more recent predictions using the Dyson-Schwinger Equation approach. We also present analysis of the unpolarized cross section data, which contributes to the g1 spin structure function and eventually the a2 matrix element, an x2-weighted moment of g1. The extracted a2 data are compared to a Lattice QCD calculation. / Physics
| Identifer | oai:union.ndltd.org:TEMPLE/oai:scholarshare.temple.edu:20.500.12613/2863 |
| Date | January 2014 |
| Creators | Flay, David |
| Contributors | Meziani, Zein-Eddine, Martoff, Charles Jeffrey, Napolitano, Jim, Surrow, Bernd, Gamberg, Leonard P. |
| Publisher | Temple University. Libraries |
| Source Sets | Temple University |
| Language | English |
| Detected Language | English |
| Type | Thesis/Dissertation, Text |
| Format | 339 pages |
| Rights | IN COPYRIGHT- This Rights Statement can be used for an Item that is in copyright. Using this statement implies that the organization making this Item available has determined that the Item is in copyright and either is the rights-holder, has obtained permission from the rights-holder(s) to make their Work(s) available, or makes the Item available under an exception or limitation to copyright (including Fair Use) that entitles it to make the Item available., http://rightsstatements.org/vocab/InC/1.0/ |
| Relation | http://dx.doi.org/10.34944/dspace/2845, Theses and Dissertations |
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