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arXiv · 1305.0292

Insights into the gamma* N -> Delta transition

Jorge Segovia·Chen Chen·Craig D. Roberts·Shaolong Wan
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Abstract

The γ* N -> Δ(1232) transition is a window on hadron shape deformation, the applicability of perturbative QCD at moderate momentum transfers, and the influence of nonperturbative phenomena on hadronic observables. We explain that the Ash-convention magnetic transition form factor must fall faster than the neutron's magnetic form factor and nonzero values for the associated quadrupole ratios reveal the impact of quark orbital angular momentum within the nucleon and Δ(1232); and show that these quadrupole ratios do approach their predicted asymptotic limits, albeit slowly.

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Jorge Segovia, Chen Chen, Craig D. Roberts, Shaolong Wan. 2013-09-10. Insights into the gamma* N -> Delta transition. https://doi.org/10.1103/physrevc.88.032201

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