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arXiv · hep-ph/0209179

Impact Parameter Dependent Parton Distributions and Transverse Single Spin Asymmetries

Matthias Burkardt
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Abstract

Generalized parton distributions (GPDs) with purely transverse momentum transfer can be interpreted as Fourier transforms of the distribution of partons in impact parameter space. The helicity-flip GPD $E(x,0,-\Dps)$ is related to the distortion of parton distribution functions in impact parameter space if the target is not a helicity eigenstate, but has some transverse polarization. This transverse distortion can be used to develop an intuitive explanation for various transverse single spin asymmetries.

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Matthias Burkardt. 2002-10-29. Impact Parameter Dependent Parton Distributions and Transverse Single Spin Asymmetries. https://doi.org/10.1103/physrevd.66.114005

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