# D*Dpi coupling constant in 2+1 flavor lattice QCD

Developments in high-performance computing instruments and advancements in the numerical algorithms combined with lattice gauge theory make it possible to simulate Quantum Chromodynamics (QCD), the theory of strongly-interacting quarks and gluons, numerically at nearly physical light-quark masses. In this work we present our results for the $D^*D\pi$ coupling constant as simulated on $32^3 \times 64$, unquenched $2+1$-flavor lattices. We estimate the coupling at the chiral limit as $g_{D^*D\pi} = 16.23 \pm 1.71$, which is in good agreement with its experimental value $g^{(exp)}_{D^*D\pi} = 17.9\pm0.3\pm1.9$ as obtained by CLEO II Collaboration.