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CP Violation in Hadronic tau Decays

Alakabha Datta·Ken Kiers·David London·Patrick J. O'Donnell·Alejandro Szynkman
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Abstract

We re-examine CP violation in the Delta S = 0 decays tau -> N pi nu_tau (N=2,3,4). We assume that the new physics (NP) is a charged Higgs. We show that there is no NP contribution to tau -> pi pi nu_tau, which means that no CP violation is expected in this decay. On the other hand, NP can contribute to tau -> N pi nu_tau (N=3,4). These are dominated by the intermediate resonant decays tau -> omega pi nu_tau, tau -> rho pi nu_tau and tau -> a_1 pi nu_tau. We show that the only sizeable CP-violating effects which are possible are in tau -> a_1 pi nu_tau -> 4 pi nu_tau (polarization-dependent rate asymmetry) and tau -> omega pi nu_tau (triple-product asymmetry).

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Alakabha Datta, Ken Kiers, David London, Patrick J. O'Donnell, Alejandro Szynkman. 2007-02-24. CP Violation in Hadronic tau Decays. https://doi.org/10.1103/physrevd.75.074007%2010.1103%2Fphysrevd.76.079902

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