The Standard Model confronts CP violation in D0→ π+π and D0→ K+K

Article

Abstract

The recently measured direct CP asymmetries in the processes D0→ π+π and D0→ K+K show a significant deviation from the naive Standard Model expecta- tion. Using a general parameterization of the decay amplitudes, we show that the measured branching ratios imply large SU(3) breaking and large violations of the naive 1/Nc counting. Furthermore, rescattering constrains the I = 0 amplitudes in the ππ and KK channels. Combining all this information, we show that, with present errors, the observed asymme- tries are marginally compatible with the Standard Model. Improving the experimental accuracy could lead to an indirect signal of new physics.

Keywords

Rare Decays Heavy Quark Physics CP violation 

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Copyright information

© SISSA, Trieste, Italy 2012

Authors and Affiliations

  • Enrico Franco
    • 1
  • Satoshi Mishima
    • 1
  • Luca Silvestrini
    • 1
  1. 1.INFNRomaItaly

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