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arXiv · 0805.3068

Pseudoscalar-meson--octet-baryon coupling constants in two-flavor lattice QCD

G. Erkol·M. Oka·T. T. Takahashi
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Abstract

We evaluate the $πN!N$, $πΣΣ$, $πΛΣ$, $KΛN$ and $K ΣN $ coupling constants and the corresponding monopole masses in lattice QCD with two flavors of dynamical quarks. The parameters representing the SU(3)-flavor symmetry are computed at the point where the three quark flavors are degenerate at the physical $s$-quark mass. In particular, we obtain $α\equiv F/(F+D)=0.395(6)$. The quark-mass dependences of the coupling constants are obtained by changing the $u$- and the $d$-quark masses. We find that the SU(3)-flavor parameters have weak quark-mass dependence and thus the SU(3)-flavor symmetry is broken by only a few percent at each quark-mass point we consider.

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G. Erkol, M. Oka, T. T. Takahashi. 2009-04-14. Pseudoscalar-meson--octet-baryon coupling constants in two-flavor lattice QCD. https://doi.org/10.1103/physrevd.79.074509

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