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arXiv · 1107.5755

Constraining quark angular momentum through semi-inclusive measurements

Alessandro Bacchetta·Marco Radici
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Abstract

The determination of quark angular momentum requires the knowledge of the generalized parton distribution E in the forward limit. We assume a connection between this function and the Sivers transverse-momentum distribution, based on model calculations and theoretical considerations. Using this assumption, we show that it is possible to fit at the same time nucleon magnetic moments and semi-inclusive single-spin asymmetries. This imposes additional constraints on the Sivers function and opens a plausible way to quantifying quark angular momentum.

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Alessandro Bacchetta, Marco Radici. 2012-02-14. Constraining quark angular momentum through semi-inclusive measurements. https://doi.org/10.1103/physrevlett.107.212001

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