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arXiv · 0808.2374

Gluonic Pole Matrix Elements in Spectator Models

A. Mukherjee·L. Gamberg·P. J. Mulders
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Abstract

We investigate the gluonic pole matrix element contributing to the first $p_T$ moment of the distribution and fragmentation functions in a spectator model. By performing a spectral analysis, we find that for a large class of spectator models, the contribution of gluonic pole matrix elements is non-zero for the distribution correlators, whereas in fragmentation correlators they vanish. This outcome is important in the study of universality for fragmentation functions.

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A. Mukherjee, L. Gamberg, P. J. Mulders. 2008-08-18. Gluonic Pole Matrix Elements in Spectator Models. https://doi.org/10.1142/9789814277785_0031

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