We present the results of the first lattice QCD study of the strong coupling g_{D^* D pi}. From our simulations in the quenched approximation, we obtain g_{D^* D pi} = 18.8 +/- 2.3^{+1.1}_{-2.0} and hat(g)_c = 0.67 +/- 0.08^{+0.04}_{-0.06}. Whereas previous theoretical studies gave different predictions, our result favours a large value for hat(g)_c. It agrees very well with the recent experimental value by CLEO. hat(g) varies very little with the heavy mass and we find in the infinite mass limit hat(g)_infinity = 0.69(18).
Cite
@article{arxiv.hep-ph/0206237,
title = {First lattice QCD estimate of the g_{D^* D pi} coupling},
author = {A. Abada and D. Becirevic and Ph. Boucaud and G. Herdoiza and J. P. Leroy and A. Le Yaouanc and O. Pene and J. Rodríguez-Quintero},
journal= {arXiv preprint arXiv:hep-ph/0206237},
year = {2016}
}
Comments
24 pages, 7 figures; references added, corrected typos, Comments added about the continuum limit