$D^*Dρ$ and $B^*Bρ$ strong couplings in light-cone sum rules

Abstract

We present an improved calculation of the strong coupling constants g D * Dρ and g B * Bρ in lightcone sum rules including the one-loop QCD corrections of leading power with ρ meson distribution amplitudes. We further compute the subleading-power corrections from two-particle and threeparticle higher-twist contributions at leading order up to twist-4 accuracy. The next-to leading order corrections to leading power contribution offset the subleading-power corrections to certain extend numerically, and our numerical results are consistent with previous works from sum rules.The comparisons between our results and the existing model-dependent estimations are also made.