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arXiv · 1509.03311

Contact-interaction Faddeev equation and, inter alia, proton tensor charges

Shu-Sheng Xu·Chen Chen·Ian C. Cloet·Craig D. Roberts·Jorge Segovia·Hong-Shi Zong
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Abstract

A confining, symmetry-preserving, Dyson-Schwinger equation treatment of a vector-vector contact interaction is used to formulate Faddeev equations for the nucleon and Delta-baryon in which the kernel involves dynamical dressed-quark exchange and whose solutions therefore provide momentum-dependent Faddeev amplitudes. These solutions are compared with those obtained in the static approximation and with a QCD-kindred formulation of the Faddeev kernel. They are also used to compute a range of nucleon properties, amongst them: the proton's sigma-term; the large Bjorken-x values of separate ratios of unpolarised and longitudinally-polarised valence u- and d-quark parton distribution functions; and the proton's tensor charges, which enable one to directly determine the effect of dressed-quark electric dipole moments (EDMs) on neutron and proton EDMs.

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Shu-Sheng Xu, Chen Chen, Ian C. Cloet, Craig D. Roberts, Jorge Segovia, Hong-Shi Zong. 2015-12-01. Contact-interaction Faddeev equation and, inter alia, proton tensor charges. https://doi.org/10.1103/physrevd.92.114034

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