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arXiv · 0811.2368

Studying the Sivers function by model calculations

A. Courtoy·S. Scopetta·V. Vento
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Abstract

A formalism is presented to evaluate the Sivers function in constituent quark models. A non-relativistic reduction of the scheme is performed and applied to the Isgur-Karl model. The sign for the $u$ and $d$ flavor contributions that we obtained turns out to be opposite. The Burkardt Sum Rule is fulfilled to a large extent. After the estimate of the QCD evolution of the results from the momentum scale of the model to the experimental one, a reasonable agreement with the available data is obtained.

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A. Courtoy, S. Scopetta, V. Vento. 2008-12-15. Studying the Sivers function by model calculations. https://doi.org/10.1063/1.3122171

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