We present a first Nf=2 lattice estimate of the hadronic coupling
g12 which parametrizes the strong decay of a radially excited B∗ meson
into the ground state B meson at zero recoil. We work in the static limit of
Heavy Quark Effective Theory (HQET) and solve a Generalised Eigenvalue Problem
(GEVP), which is necessary for the extraction of excited state properties.
After an extrapolation to the continuum limit and a check of the pion mass
dependence, we obtain g12=−0.17(4).Comment: Proceedings of the 31st International Symposium on Lattice Field
Theory (Lattice 2013), 29 July - 3 August 2013, Mainz, German