Effective Hamiltonian for B→Xse+e- beyond leading logarithms in the naive dimensional regularization and 't Hooft-Veltman schemes

We calculate the next-to-leading QCD corrections to the effective Hamiltonian for B→Xse+e- in the NDR and tHV schemes. We give for the first time analytic expressions for the Wilson coefficient of the operator Q9=(s̄b)V-A(ēe)V in the NDR and HV schemes. Calculating the relevant matrix elements of local operators in the spectator model we demonstrate the scheme independence of the resulting short-distance contribution to the physical amplitude. Keeping consistently only leading and next-to-leading terms, we find an analytic formula for the differential dilepton invariant mass distribution in the spectator model. A numerical analysis of the mt, ΛMS̄, and μ=O(mb) dependences of this formula is presented. We compare our results with those given in the literature.