Polarized proton structure in the resonance region

Abstract

In view of the precise data available on inclusive polarized electron scattering off polarized proton targets in the nucleon resonance excitation region, we compare these results with the coherent sum of resonant contributions to the polarized structure function $g_1$ and virtual photon asymmetry $A_1$. To this goal, we employ the nucleon resonance electroexcitation amplitudes determined for photon virtualities $Q^2$ $<$ 5.0 GeV${}^2$ from analyses of the CLAS data on exclusive electroproduction off protons in the resonance region. Most of the well established resonances of four star PDG status in the mass range up to 1.75~GeV are included. We find that the resonance-like structures observed in the inclusive $g_1$ data are related to the resonant contributions in the entire range of photon virtuality $Q^2$ where the data on $g_1$ are available. In the range of invariant mass of the final hadron system $W$ $>$ 1.5 GeV, the data on the asymmetry $A_1$ are well reproduced even when accounting for resonant contributions only, especially for the larger values of $Q^2$ and energies analysed. This observation offers an interesting hint to quark-hadron duality seen in polarized inclusive electron scattering observables.

Contribution to proceedings: Emergence and Structure of Baryons - Selected Contributions from the International Conference Baryons 2022

References in corpus (7)

• A study of the $P_{11}(1440)$ and $D_{13}(1520)$ resonances from CLAS data on $ep\to e^{\prime }{\pi }^{+}{\pi }^{-}{p}^{\prime }$
• Parton Distributions in Nucleons and Nuclei
• Determination of the Proton Spin Structure Functions for 0.05 < Q^2 < 5 GeV^2 using CLAS
• Measurements of $ep\to e^{\prime }{\pi }^{+}n$ at W = 1.6 - 2.0 GeV and extraction of nucleon resonance electrocouplings at CLAS
• Proton Spin Structure in the Resonance Region
• Strong QCD Insights from Excited Nucleon Structure Studies with CLAS and CLAS12
• Evidence for the $N^{\prime }(1720)3/2^{+}$ Nucleon Resonance from Combined Studies of CLAS ${\pi }^{+}{\pi }^{-}p$ Photo- and Electroproduction Data