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arXiv · 0711.0610

Studying pion effects in the quark propagator

Dominik Nickel·Christian S. Fischer·Jochen Wambach
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Abstract

Within the framework of Schwinger-Dyson and Bethe-Salpeter equations we investigate the importance of pions for the quark-gluon interaction. To this end we choose a truncation for the quark-gluon vertex that includes intermediate pion degrees of freedom and adjust the interaction such that unquenched lattice results for various current quark masses are reproduced. The corresponding Bethe-Salpeter kernel is constructed from constraints by chiral symmetry. After extrapolation to the physical point we find a considerable contribution of the pion back reaction to the quark mass function as well as to the chiral condensate. The quark wave function is less affected.

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Dominik Nickel, Christian S. Fischer, Jochen Wambach. 2007-11-05. Studying pion effects in the quark propagator. https://doi.org/10.1016/j.ppnp.2007.12.045

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