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arXiv · 2301.06118

Transverse momentum-dependent parton distributions for longitudinally polarized nucleons from domain wall fermion calculations at the physical pion mass

M. Engelhardt·N. Hasan·T. Izubuchi·C. Kallidonis·S. Krieg·S. Meinel·J. Negele·A. Pochinsky·G. Silvi·S. Syritsyn
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Abstract

Previous Lattice QCD calculations of nucleon transverse momentum-dependent parton distributions (TMDs) focused on the case of transversely polarized nucleons, and thus did not encompass two leading-twist TMDs associated with longitudinal polarization, namely, the helicity TMD and the worm-gear TMD corresponding to transversely polarized quarks in a longitudinally polarized nucleon. Based on a definition of TMDs via hadronic matrix elements of quark bilocal operators containing staple-shaped gauge connections, TMD observables characterizing the aforementioned two TMDs are evaluated, utilizing an RBC/UKQCD domain wall fermion ensemble at the physical pion mass.

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M. Engelhardt, N. Hasan, T. Izubuchi, C. Kallidonis, S. Krieg, S. Meinel, J. Negele, A. Pochinsky, G. Silvi, S. Syritsyn. 2023-01-15. Transverse momentum-dependent parton distributions for longitudinally polarized nucleons from domain wall fermion calculations at the physical pion mass. https://arxiv.org/abs/2301.06118

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