The tau weak-magnetic dipole moment

J. Bernabéu; G. A. González-Sprinberg; M. Tung; J. Vidal

doi:10.1016/0550-3213(94)00525-j

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arXiv · hep-ph/9411289

The tau weak-magnetic dipole moment

J. Bernabéu·G. A. González-Sprinberg·M. Tung·J. Vidal

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Abstract

We calculate the prediction for the anomalous weak-magnetic form factor of the tau lepton at $q^2=M_Z^2$ within the Standard Model. With all particles on-shell, this is a electroweak gauge invariant quantity. Its value is $a_τ^w (M_Z^2)= - \;(2.10 + 0.61\, i) \times 10^{-6}$. We show that the transverse and normal components of the single-tau polarization of tau pairs produced at $e^+e^-$ unpolarized collisions are sensitive to the real and absorptive parts of the anomalous weak-magnetic dipole moment of the tau. The sensitivity one can achieve at LEP in the measurement of this dipole moment is discussed.

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J. Bernabéu, G. A. González-Sprinberg, M. Tung, J. Vidal. 1994-11-15. The tau weak-magnetic dipole moment. https://doi.org/10.1016/0550-3213(94)00525-j

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