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Sum rules for higher-twist parton distributions

M. Burkardt
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Abstract

In deep-inelastic scattering experiments, there is a general connection between subtractions in dispersion relations, violations of sum-rules and $δ$-functions in parton distribution functions. It is explained why one might expect a small violation in sum rules for the twist-3 distribution functions $g_T(x)$ and $h_L(x)$ when the sum-rules are applied to $x\neq 0$ data only. The non-perturbative predictions are studied in the context of a one-loop model.

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M. Burkardt. 1999-08-26. Sum rules for higher-twist parton distributions. https://arxiv.org/abs/hep-ph/9908479

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