Annihilation diagrams and D meson decays

Two mechanisms of heavy meson decay are analyzed for explanation of the found difference in the lifetime of D0- and D+-mesons. An analytical evaluation of contribution of the annihilation process to widths of nonlepton decays of D0-mesons is carried out. The calculated value oGITAsub(annih)/GITAsub(decay) width ratio makes up <0.3. Thus, the contribution of annihilation diagrams to widths of nonlepton decay turus to be three times less than the contribution from the quark decay. It is noted that if dominance of the annihilation mechanism in weak process is proved in further experimental investigation it would be necessary to take into account more complex configurations in wave functions of hadrons instead of single-gluon approximation