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arXiv · nucl-th/0304003

Analysis of a quenched lattice-QCD dressed-quark propagator

Abstract

Quenched lattice-QCD data on the dressed-quark Schwinger function can be correlated with dressed-gluon data via a rainbow gap equation so long as that equation's kernel possesses enhancement at infrared momenta above that exhibited by the gluon alone. The required enhancement can be ascribed to a dressing of the quark-gluon vertex. The solutions of the rainbow gap equation exhibit dynamical chiral symmetry breaking and are consistent with confinement. The gap equation and related, symmetry-preserving ladder Bethe-Salpeter equation yield estimates for chiral and physical pion observables that suggest these quantities are materially underestimated in the quenched theory: | | by a factor of two and f_pi by 30%.

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M. S. Bhagwat, M. A. Pichowsky, C. D. Roberts, P. C. Tandy. 2003-04-01. Analysis of a quenched lattice-QCD dressed-quark propagator. https://doi.org/10.1103/physrevc.68.015203

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