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arXiv · 0812.3783

Partonic Pole Matrix Elements for Fragmentation

S. Meissner·A. Metz
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Abstract

A model-independent analysis of collinear three-parton correlation functions for fragmentation is performed. By investigating their support properties it is shown, in particular, that the so-called partonic pole matrix elements vanish. This sheds new light on the understanding of transverse single spin asymmetries in various hard semi-inclusive reactions. Moreover, it gives additional strong evidence for the universality of transverse-momentum-dependent fragmentation functions.

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S. Meissner, A. Metz. 2009-05-05. Partonic Pole Matrix Elements for Fragmentation. https://doi.org/10.1103/physrevlett.102.172003

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