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arXiv · 1910.08298

Evaluation of pion-nucleon sigma term in Dyson-Schwinger equation approach of QCD

Jing-Hui Huang·Ting-Ting Sun·Huan Chen
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Abstract

We calculate the variation of the chiral condensate in medium with respect to the quark chemical potential and evaluate the pion-nucleon sigma term via the Hellmann-Feynman theorem. The variation of chiral condensate in medium are obtained by solving the truncated Dyson-Schwinger equation for quark propagator at finite chemical potential, with different models for the quark-gluon vertex and gluon propagator. We obtain the value of the sigma term $σ_{πN}$ = 62(1)(2) MeV, where the first represents the systematic error due to our different model for the quark-gluon vertex and gluon propagator and the second represents a statistical error in our linear fitting procedure.

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Jing-Hui Huang, Ting-Ting Sun, Huan Chen. 2020-03-26. Evaluation of pion-nucleon sigma term in Dyson-Schwinger equation approach of QCD. https://doi.org/10.1103/physrevd.101.054007

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