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arXiv · 0912.3711

Bethe-Salpeter equations: mesons beyond the rainbow-ladder truncation

Richard Williams·Christian S. Fischer
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Abstract

We investigate masses of light mesons from a coupled system of Dyson--Schwinger (DSE) and Bethe--Salpeter equations (BSE), taking into account dominant non-Abelian, sub-leading Abelian, and dominant pion cloud contributions to the dressed quark-gluon vertex. The axial-vector Ward-Takahashi identity preserving Bethe-Salpeter kernel is constructed and the spectrum of light mesons calculated. Our model goes significantly beyond the rainbow-ladder. We find that sub-leading Abelian corrections are further dynamically suppressed, and that our results supersede early qualitative predictions from simple truncation schemes.

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Richard Williams, Christian S. Fischer. 2009-12-18. Bethe-Salpeter equations: mesons beyond the rainbow-ladder truncation. https://arxiv.org/abs/0912.3711

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