Semileptonic Form Factors of Heavy-light Mesons from Lattice Qcd

The form factors for the semileptonic decays of heavy-light pseudoscalar mesons of the type D ! Kee are studied in quenched lattice QCD at = 6:0 using Wilson fermions. We explore new numerical techniques for improving the signal and study O(a) corrections using three diierent lattice transcriptions of the vector current. We present a detailed discussion of the relation of these lattice currents to the continuum vector current and show that the disagreement between the previous results is to a large extent due to the value of Z V used in the calculations. We also present results for the decay constants of light-light, heavy-light and heavy-heavy mesons.