Semi-leptonic decays heavy-light to heavy-light

We present results for the QCD matrix elements involved in semi-leptonic de cays of B-mesons into pseudo scalar heavy light states. The application of NRQCD heavy quarks allows for quark masses around the physical b-quark. We investigate the dependence of the form factors on the external momenta and looked at the mass dependence at zero recoil. For the first time, results f or radially excited decay products are presented.