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arXiv · 0905.3118

What can we learn from the breaking of the Wandzura-Wilczek relation?

Alberto Accardi·Alessandro Bacchetta·Marc Schlegel
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Abstract

We review the study the Wandzura-Wilczek relation for the structure function g_2, with a particular attention on the connection with the framework of Transverse Momentum Dependent factorization. We emphasize that the relation is broken by two distinct twist-3 terms. In the light of these findings, we clarify what can be deduced from the available experimental data on g_2, which indicate a breaking of the order 20-40%, and how to individually measure the twist-3 terms.

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Alberto Accardi, Alessandro Bacchetta, Marc Schlegel. 2009-05-19. What can we learn from the breaking of the Wandzura-Wilczek relation?. https://arxiv.org/abs/0905.3118

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