SU(3) breaking corrections to the $D$, $D^{\ast }$, $B$, and $B^{\ast }$ decay constants

M. Altenbuchinger, L. S. Geng, W. Weise

We report on a first next-to-next-to-leading order calculation of the decay constants of the $D$ ($D^{\ast }$) and $B$ ($B^{\ast }$) mesons using a covariant formulation of chiral perturbation…