Semileptonic decays of D(s) mesons

A symmetry-preserving continuum approach to meson bound states in quantum field theory, employed elsewhere to describe numerous pi- and K-meson electroweak processes, is used to analyze leptonic and semileptonic decays of D-(s) mesons. Each semileptonic transition is conventionally characterized by the value of the dominant form factor at t = 0 and the following results are obtained herein: f(1)(Ds -> K)(0) = 0.673(40); f(+)(D ->pi)(0) = 0.618(31) and f(+)(D -> K)(0) = 0.756(36). Working with the computed t-dependence of these form factors and standard averaged values for vertical bar V-cd vertical bar, vertical bar V-cs vertical bar, onr arrives at the following predictions for associated branching fractions: BDs+ (-> K0e+nu epsilon) = 3.31(33) x 10(-3), B-D(0) (->pi-e+nu epsilon) = 2.73(22) x 10(-3), and B-D(0) (-> K-e+nu epsilon) = 3.83(28)%. Alternatively, using the calculated t-dependence, agreement with contemporary empirical results for these branching fractions requires vertical bar V-cd vertical bar = 0.221(9), vertical bar V-us vertical bar = 0.953(34). With all D-(s) transitions form factors in hand, the nature of SU(3)-flavor symmetry breaking in this array of processes can be analysed; and just as in the pi-K sector, the magnitude of such effects is found to be determined by the scales associated with emergent mass generation in the Standard Model, not those originating with the Higgs mechanism.