Dπ Form Factor Revisited
نویسندگان
چکیده
The D * Dπ form factor is evaluated in a QCD sum rule calculation for both D and π off-shell mesons. We study the Borel sum rule for the three point function of one pseudoscalar, one axial and one vector meson currents. We find that the momentum dependence of the form factors is very different if the D or the π meson is off-shell, but they lead to the same coupling constant in the D * Dπ vertex.
منابع مشابه
Non-factorizable contributions in B decays revisited
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We reanalyze B → Dπ and B → KJ/ψ data to extract a set of parameters which give the relevant hadronic matrix elements in terms of factorized amplitudes. Various sources of theoretical uncertainties are studied, in particular those depending on the model adopted for the form factors. We find that the fit to the B → Dπ branching ratios substantially depends on the model describing the Isgur-Wise ...
متن کاملep - p h / 98 10 27 1 v 1 7 O ct 1 99 8 ROME 1 - 1222 / 98 Heavy - heavy form factors and generalized factorization
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