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arXiv · 1010.4556

A model independent analysis of gluonic pole matrix elements and universality of TMD fragmentation functions

Leonard Gamberg·Asmita Mukherjee·Piet J. Mulders
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Abstract

Gluonic pole matrix elements explain the appearance of single spin asymmetries (SSA) in high-energy scattering processes. They involve a combination of operators which are odd under time reversal (T-odd). Such matrix elements appear in principle both for parton distribution functions and parton fragmentation functions. We show that for parton fragmentation functions these gluonic pole matrix elements vanish as a consequence of the analytic structure of scattering amplitudes in Quantum Chromodynamics. This result is important in the study of the universality of transverse momentum dependent (TMD) fragmentation functions.

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Leonard Gamberg, Asmita Mukherjee, Piet J. Mulders. 2010-10-21. A model independent analysis of gluonic pole matrix elements and universality of TMD fragmentation functions. https://doi.org/10.1103/physrevd.83.071503

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