Chiral mechanism of breaking the ΔT=1 rule in nonleptonic weak decays of charmed hadrons

The phenomenological chiral Lagrangian is proposed for description of nonleptonic weak decays of hadrons violating the selection rule Δ T=1. The amplitudes of two-body nonleptonic decays of charmed mesons are calculated. The theoretical ratios of decay probabilities (except for D deg →π+π- and D deg → K+K-) are in satisfactory agreement with the available experimental data. By means of derived Lagrangian the estimation of the mass difference of neutral D mesons is made. It is shown that the difference is generally due to the virtual single-meson states the contribution of which is equal to 3x10-6 eV that does not contradict the experiment