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arXiv · hep-ph/9812373

Tau weak dipole moments from azimuthal asymmetries

J. Vidal·J. Bernabeu·G. Gonzalez-Sprinberg
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Abstract

We show that transverse and normal single-$tau$ polarization of $tau$ pairs produced at $e^+$ $e^-$ unpolarized collisions, at the $Z$ peak, are sensitive to weak (magnetic and electric) dipole moments of the $tau$. We also show how these components of the $τ$ polarization are accessible by measuring appropriate azimuthal asymmetries in the angular distribution of its decay products. Sensitivities of the order of $10^{-18}$ $e\cdot cm$, for the weak-electric dipole moment, and $10^{-4}$ ($10^{-3}$), for the real (imaginary) part of the weak-magnetic dipole moment of $τ$, may be achieved. Compatible bounds are also presented from spin-spin correlated asymmetries.

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J. Vidal, J. Bernabeu, G. Gonzalez-Sprinberg. 1998-12-15. Tau weak dipole moments from azimuthal asymmetries. https://doi.org/10.1016/s0920-5632(99)00471-5

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