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arXiv · 1903.05661

Experimental studies at low $Q^2$ of the spin structure of the nucleon at Jefferson Lab

A. Deur
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Abstract

We summarize the experimental program of Jefferson Lab that studies the nucleon spin structure at low $Q^2$. This program completes the precise experimental mapping of the nucleon spin structure functions $g_1(\nu, Q^2)$ and $g_2(\nu, Q^2)$ and their moments started at SLAC, CERN and DESY at high $Q^2$, and continued at Jefferson Lab at intermediate $Q^2$. The results presented cover the domain where Chiral Effective Field Theory ($\chi$EFT) should describe the strong interaction. They provide a comprehensive set of benchmark measurements for $\chi$EFT. The preliminary conclusion is that nucleon spin structure data are still challenging for $\chi$EFT in spite of the notable improvements in these calculations.

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A. Deur. 2019-03-13. Experimental studies at low $Q^2$ of the spin structure of the nucleon at Jefferson Lab. https://arxiv.org/abs/1903.05661

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