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Chromodynamic Lensing and $\perp$ Single Spin Asymmetries

Matthias Burkardt
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Abstract

The physical interpretation of generalized parton distributions (in the limit $ξ=0$) as Fourier transforms of impact parameter dependent parton distributions is discussed. Particular emphasis is put on the role of the target polarization. For transversely polarized targets we expect a significant deviation from axial symmetry for the distribution in the transverse plane. We conjecture that this transverse distortion, in combination with the final state provides a natural explanation for the sign of the Sivers contribution to semi-inclusive single-spin asymmetries.

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Matthias Burkardt. 2003-09-23. Chromodynamic Lensing and $\perp$ Single Spin Asymmetries. https://arxiv.org/abs/hep-ph/0309269

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