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arXiv · 1204.3557

Testing for new physics in singly Cabibbo suppressed D decays

Yuval Grossman·Alexander L. Kagan·Jure Zupan
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Abstract

We devise tests for a new physics origin of the recently measured direct CP violation in singly Cabibbo suppressed D decays. The tests take the form of sum rules for the CP asymmetries in various D decays. They are based on the fact that within the standard model CP violation arises from interference of the dominant tree amplitudes with the Delta I=1/2 penguin amplitudes. The sum rules would be violated if the observed CP violation is due to new physics contributions to the effective weak Hamiltonian that change isospin by Delta I=3/2.

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Yuval Grossman, Alexander L. Kagan, Jure Zupan. 2012-04-16. Testing for new physics in singly Cabibbo suppressed D decays. https://doi.org/10.1103/physrevd.85.114036

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