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Lepton Polarization and Forward-Backward Asymmetries in b -> s tau+ tau-

Wafia Bensalam·David London·Nita Sinha·Rahul Sinha
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Abstract

We study the spin polarizations of both tau leptons in the decay b -> s tau+ tau-. In addition to the polarization asymmetries involving a single tau, we construct asymmetries for the case where both polarizations are simultaneously measured. We also study forward-backward asymmetries with polarized tau's. We find that a large number of asymmetries are predicted to be large, >~ 10%. This permits the measurement of all Wilson coefficients and the b-quark mass, thus allowing the standard model (SM) to be exhaustively tested. Furthermore, there are many unique signals for the presence of new physics. For example, asymmetries involving triple-product correlations are predicted to be tiny within the SM, O(10^{-2}). Their observation would be a clear signal of new physics.

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Wafia Bensalam, David London, Nita Sinha, Rahul Sinha. 2002-12-09. Lepton Polarization and Forward-Backward Asymmetries in b -> s tau+ tau-. https://doi.org/10.1103/physrevd.67.034007

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