Sivers Asymmetry and Generalized Parton Distributions in Impact Parameter Space
نویسندگان
چکیده
Recently, it has been pointed out that there exists a connection between the generalized parton distribution E(x, 0, t) and the Sivers asymmetry. For transversely polarized nucleon targets, generalized parton distributions are asymmetric in impact parameter space. This impact parameter space asymmetry, together with the final state interaction of the active quark, gives rise to the Sivers asymmetry in momentum space. We demonstrate this phenomenon explicitly in the scalar diquark model. This result also illustrates the physics that underlies the correlation between the anomalous magnetic moment and the Sivers asymmetry for a given quark flavor.
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