On the $\Delta A_{CP}$ saga

Understand

We discuss a model in which the large SU(3) flavor violations in singly Cabibbo suppressed decays of neutral D mesons are ascribed exclusively to the final state interactions.

• The agreement with the experimental data on the branching ratios is obtained with large strong phase differences which are also necessary for substantial direct CP violation.
• While the value of the CP violating asymmetries depends on the strength of the penguin contribution, we predict an asymmetry for the decays into charged pions more than twice larger than that for charged kaons and having opposite sign.