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arXiv · 0902.0163

Parton Distributions in the Impact Parameter Space

Matthias Burkardt
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Abstract

Parton distributions in impact parameter space, which are obtained by Fourier transforming GPDs, exhibit a significant deviation from axial symmetry when the target and/or quark is transversely polarized. In combination with the final state interactions, this transverse deformation provides a natural mechanism for naive-T odd transverse single-spin asymmetries in semi-inclusive DIS. The deformation can also be related to the transverse force acting on the active quark in polarized DIS at higher twist.

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Matthias Burkardt. 2009-02-01. Parton Distributions in the Impact Parameter Space. https://doi.org/10.1063/1.3215727

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