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arXiv · 1607.03823

Symmetry-preserving contact interaction model for heavy-light mesons

F. E. Serna·M. A. Brito·G. Krein
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Abstract

We use a symmetry-preserving regularization method of ultraviolet divergences in a vector-vector contact interac- tion model for low-energy QCD. The contact interaction is a representation of nonperturbative kernels used Dyson-Schwinger and Bethe-Salpeter equations. The regularization method is based on a subtraction scheme that avoids standard steps in the evaluation of divergent integrals that invariably lead to symmetry violation. Aiming at the study of heavy-light mesons, we have implemented the method to the pseudoscalar pion and Kaon mesons. We have solved the Dyson-Schwinger equation for the u, d and s quark propagators, and obtained the bound-state Bethe-Salpeter amplitudes in a way that the Ward-Green-Takahashi identities reflecting global symmetries of the model are satisfied for arbitrary routing of the momenta running in loop integrals.

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F. E. Serna, M. A. Brito, G. Krein. 2016-07-13. Symmetry-preserving contact interaction model for heavy-light mesons. https://doi.org/10.1063/1.4938727

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