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arXiv · 1808.10560

A Note on Pretzelosity TMD Parton Distribution

X. P. Chai·K. B. Chen·J. P. Ma
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Abstract

We show that the transverse-momentum-dependent parton distribution, called as Pretzelosity function, is zero at any order in perturbation theory of QCD for a single massless quark state. This implies that Pretzelosity function is not factorized with the collinear transversity parton distribution at twist-2, when the struck quark has a large transverse momentum. Pretzelosity function is in fact related to collinear parton distributions defined with twist-4 operators. In reality, Pretzelosity function of a hadron as a bound state of quarks and gluons is not zero. Through an explicit calculation of Pretzelosity function of a quark combined with a gluon nonzero result is found.

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X. P. Chai, K. B. Chen, J. P. Ma. 2019-03-03. A Note on Pretzelosity TMD Parton Distribution. https://doi.org/10.1016/j.physletb.2018.12.020

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