Determination of the strong g-coupling and of the ${\mu }_{B^{\ast }B\gamma }-$ strength from two-photon decays of heavy vector mesons

Dafne Guetta, Paul Singer

We describe a calculation of the two-photon decays of heavy vector-mesons, $B^{\ast }\to B\gamma \gamma$ and $D^{\ast }\to D\gamma \gamma$, by using the ``heavy meson chiral Lagrangian''. The decay amplitudes are e…