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arXiv · hep-ph/9304265

Chiral Dynamics and Heavy Quark Symmetry in a Toy Field Theoretic Model

William A. Bardeen·Christopher T. Hill
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Abstract

We study a solvable QCD--like toy theory, a generalization of the Nambu--Jona-Lasinio model, which implements chiral symmetries of light quarks and heavy quark symmetry. The chiral symmetric and chiral broken phases can be dynamically tuned. This implies a parity doubled heavy--light meson system, corresponding to a $(0^-,1^-)$ multiplet and a $(0^+,1^+)$ heavy spin multiplet. Consequently the mass difference of the two multiplets is given by a Goldberger--Treiman relation and $g_A$ is found to be small. The Isgur--Wise function, $ξ(w)$, the decay constant, $f_B$, and other observables are studied.

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William A. Bardeen, Christopher T. Hill. 1993-04-16. Chiral Dynamics and Heavy Quark Symmetry in a Toy Field Theoretic Model. https://doi.org/10.1103/physrevd.49.409

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