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arXiv · hep-ph/0601171

The Construction of Gauge-Links in Arbitrary Hard Processes

C. J. Bomhof·P. J. Mulders·F. Pijlman
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Abstract

Transverse momentum dependent parton distribution and fragmentation functions are described by hadronic matrix elements of bilocal products of field operators off the light-cone. These bilocal products contain gauge-links, as required by gauge-invariance. The gauge-links are path-ordered exponentials connecting the field operators along a certain integration path. This integration path is process-dependent, depending specifically on the short-distance partonic subprocess. In this paper we present the technical details needed in the calculation of the gauge-links and a calculational scheme is provided to obtain the gauge-invariant distribution and fragmentation correlators corresponding to a given partonic subprocess.

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C. J. Bomhof, P. J. Mulders, F. Pijlman. 2006-01-20. The Construction of Gauge-Links in Arbitrary Hard Processes. https://doi.org/10.1140/epjc%2Fs2006-02554-2

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