A high statistics lattice calculation of using the clover action

Abstract We present a calculation of ƒ B in the static limit, obtained by numerical simulation of quenched QCD, at β =6.2 on a 18 3 × 64 lattice, using the SW-Clover quark action. The decay constant has been extracted by studying heavy (static)-light correlation functions of different smeared operators, on a sample of 220 gauge field configurations. We have obtained ƒ B static =(290±15±45) MeV , where the first error comes from the uncertainty in the determination of the matrix element and the second comes from the uncertainty in the lattice spacing. We also obtain M B s − M B d =(70±10) MeV and ƒ B s stat /ƒ B d stat =1.11 (3) . A comparison of our results with other calculations of the same quantity is made.