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Checking the Burkardt sum rule for the Sivers function by model calculations

K. Goeke·S. Meissner·A. Metz·M. Schlegel
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Abstract

The Sivers mechanism gives rise to a non-zero average transverse momentum of partons inside a transversely polarized target. According to a sum rule of Burkardt this transverse momentum vanishes when summing over all partons. We explicitly check the Burkardt sum rule by means of one-loop calculations for a quark target in perturbative QCD and for a diquark spectator model of the nucleon. In both cases the sum rule is fulfilled.

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K. Goeke, S. Meissner, A. Metz, M. Schlegel. 2006-05-08. Checking the Burkardt sum rule for the Sivers function by model calculations. https://doi.org/10.1016/j.physletb.2006.05.004

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