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arXiv · 0903.5461

Sketching the Bethe-Salpeter kernel

Lei Chang·Craig D. Roberts
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Abstract

An exact form is presented for the axial-vector Bethe-Salpeter equation, which is valid when the quark-gluon vertex is fully dressed. A Ward-Takahashi identity for the Bethe-Salpeter kernel is derived therefrom and solved for a class of dressed quark-gluon vertex models. The solution provides a symmetry-preserving closed system of gap and vertex equations. The analysis can be extended to the vector equation. This enables a comparison between the responses of pseudoscalar- and scalar meson masses to nonperturbatively dressing the quark-gluon vertex. The result indicates that dynamical chiral symmetry breaking enhances spin-orbit splitting in the meson spectrum.

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Lei Chang, Craig D. Roberts. 2009-03-31. Sketching the Bethe-Salpeter kernel. https://doi.org/10.1103/physrevlett.103.081601

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