
We present results of a lattice computation of the matrix elements of the vector and axialvector currents which are relevant for the semileptonic decays D→K and D→K∗. The computations are performed in the quenched approximation to lattice QCD on a 243×48 lattice at β=6.2, using an O(a)improved fermionic action. In the limit of zero lepton masses the semileptonic decays D→K and D→K∗ are described by four form factors: f+K,V,A1 and A2, which are functions of q2, where qμ is the fourmomentum transferred in the process. Our results for these form factors at q2=0 are: $f^+_K(0)=0.67 \er{7}{8}$ , $V(0)=1.01 \err{30}{13}$ , $A_1(0)=0.70 \err{7}{10}$ , $A_2(0)=0.66 \err{10}{15}$ , which are consistent with the most recent experimental world average values. We have also determined the q2 dependence of the form factors, which we find to be reasonably well described by a simple poledominance model. Results for other form factors, including those relevant to the decays \dpi and \drho, are also given.


Bowler, Ken C. Hazel, Nick Hoeber, Henning Kenway, Richard D. Richards, D.G. Lellouch, Laurent Nieves Pamplona, Juan Miguel Sachrajda, Christopher T. Wittig, Hartmut 1995 Improved lattice study of semileptonic decays of dmesons Physical Review D 51 9 4905 4923 