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arXiv · hep-ph/0102278

The Collins function: a simple model calculation

A. Bacchetta·R. Kundu·A. Metz·P. J. Mulders
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Abstract

The Collins function belongs to the class of the so-called time-reversal odd fragmentation functions. Being chiral-odd as well, it can serve as an important tool to observe the nucleon's transversity distribution in semi-inclusive DIS. Due to the possible presence of final state interactions, this function can be non-zero, though this has never been demonstrated in an explicit model calculation. We use a simple pseudoscalar coupling between pions and quarks to model the fragmentation process and we show that the inclusion of one-loop corrections generates a non-vanishing Collins function, therefore giving support to its existence from the theoretical point of view.

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A. Bacchetta, R. Kundu, A. Metz, P. J. Mulders. 2001-03-12. The Collins function: a simple model calculation. https://doi.org/10.1016/s0370-2693(01)00388-4

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