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arXiv · 0905.4079

The $g_2$ Structure Function

Matthias Burkardt
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Abstract

Polarized structure functions at low $Q^2$ have the physical interpretation of (generalized) spin polarizabilities. At high $Q^2$, the polarized parton distribution $g_2(x)$ provides access to quark-gluon correlations in the nucleon. We discuss the interpretation of the $x^2$ moment of $\bar{g}_2(x)$ as an average transverse force on quarks in deep-inelastic scattering from a transversely polarized target. Qualitative connections with generalized parton distributions are emphasized. The $x^2$ moment of the chirally-odd twist-3 parton distribution $e(x)$ provides information on the dependence of the average transverse force on the transversity of the quark.

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Matthias Burkardt. 2009-05-25. The $g_2$ Structure Function. https://arxiv.org/abs/0905.4079

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