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arXiv · hep-ph/9406324

Bounds on $g_5^Z$ from Precision LEP Measurements

S. Dawson·G. Valencia
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Abstract

The parity violating but CP conserving anomalous three-gauge-boson coupling $g_5^Z$ induces a universal contribution to the left-handed coupling of the $Z$ boson to fermions. We find that the LEP measurements of the partial $Z$ widths and lepton forward-backward asymmetries are sufficiently precise to place a bound of order $|g_5^Z|$ less than $\sim~10\%$. This bound is significantly better than what can be obtained at present from rare $K$ and $B$ meson decays.

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S. Dawson, G. Valencia. 1994-10-28. Bounds on $g_5^Z$ from Precision LEP Measurements. https://doi.org/10.1016/0370-2693(94)91031-6

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