Hadronic coupling constants of $g_{\sigma \pi \pi }$ in lattice QCD

Abstract

We investigate the coupling constant $g_{\sigma \pi \pi }$ for the hadronic decay $\sigma \to \pi \pi$ only using the relevant three-point function, which is evaluated by the moving-wall source technique with a pretty good noise-to-signal ratio. This simulation is carried out on a $40^3\times 96$ MILC gauge configuration with $N_f=2+1$ flavor of the "Asqtad" improved staggered dynamical sea quarks at the lattice spacing $a\approx 0.09$ fm. Our estimated value for this given MILC fine lattice gauge ensemble $g_{\sigma \pi \pi }=2.71(42)$ GeV.

Comments: Submitted to Chinese Physics C