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Probing anomalous right--handed current in Z b bbar vertex

Kang Young Lee
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Abstract

Motivated by $-2 σ$ deviation from the Standard Model prediction for the forward--backward asymmetry of $Z \to b \bar{b}$ decay in the LEP data, we explore the anomalous couplings of $Z b \bar{b}$ vertex through the electroweak precision test extended by including $A_{FB}^b$. We introduce a new variable $ε'_b$ to measure the anomalous right-handed coupling in $Z b \bar{b}$ vertex. Implications of our analysis on the nonuniversal contact interactions are studied and the left-right model is also considered as a possible origin of the anomalous right-handed couplings.

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Kang Young Lee. 1999-04-23. Probing anomalous right--handed current in Z b bbar vertex. https://doi.org/10.1016/s0370-2693(99)01453-7

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