Ratios of B and D meson decay constants in an improved mock meson model

We calculate the ratio fBsfBd by following the Oakes method which is based on chiral symmetry breaking, but we improve his calculation by performing the calculation of the factor 〈0bbγ5sbBs〉〈0bbγ5dbBd〉 in a mock meson model. In this calculation we improved the mock meson model by using a value of the parameter β which is obtained by the variational method in the relativistic quark model. We also calculate fDsfDd and then (fBs/fBd)/(fDs/fDd). In this method we also obtain the ratio fBs/fDs and fBd/fDd which are important for the knowledge of CP violation and B-B mixing.