Weak Decays of Heavy Mesons in the Instantaneous Bethe Salpeter Approach

In the framework of the instantaneous Bethe Salpeter equation we investigate weak decays of B and D mesons. Mesons are described as q-bar q states interacting via a mixture of a scalar and a vector confining kernel and a one gluon exchange. The model parameters are fixed by a fit to the meson mass spectrum including also the light mesons. We calculate form factors and compare our results to the pole dominance hypothesis. From a fit to ARGUS and CLEO data on B -> D* semileptonic decay we extract the Cabbibo Kobayashi Maskawa matrix element to be V_cb= (0.032+-0.003)*sqrt(1.49ps/tau_B). The Isgur Wise function is calculated utilizing the heavy quark mass limit. Finally, we give some results on non-leptonic decays.