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Meson-loop contributions to the quark condensate from the instanton vacuum

Hyun-Chul Kim·M. M. Musakhanov·M. Siddikov
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Abstract

We investigate the quark condensate of the QCD vacuum within the instanton vacuum model. We calculate the meson-loop contributions to the dynamical quark mass and quark condensate to ${\cal O}(1/N_c)$-, ${\cal O}(m/N_c)$-, and ${\cal O}((m\ln m) /N_c)$-order corrections. We find that the meson (especially pion) loops provide substantial contributions to the dynamical quark mass and as a result to the quark condensate. The results indicate that the $1/N_c$ corrections should be reconsidered in the systematical way. The present results are consistent with those from chiral perturbation theory.

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Hyun-Chul Kim, M. M. Musakhanov, M. Siddikov. 2005-11-21. Meson-loop contributions to the quark condensate from the instanton vacuum. https://doi.org/10.1016/j.physletb.2005.11.054

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