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arXiv · hep-ph/9811388

Indirect Constraints on the Triple Gauge Boson Couplings from $Z \to b \bar{b}$ Partial Width: An Update

O. J. P. Eboli·M. C. Gonzalez-Garcia·S. F. Novaes
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Abstract

We update the indirect bounds on anomalous triple gauge couplings coming from the non-universal one-loop contributions to the $Z \to b \bar{b}$ width. These bounds, which are independent of the Higgs boson mass, are in agreement with the standard model predictions for the gauge boson self-couplings since the present value of $R_b$ agrees fairly well with the theoretical estimates. Moreover, these indirect constraints on $Δg^Z_1$ and $g^Z_5$ are more stringent than the present direct bounds on these quantities, while the indirect limit on $λ_Z$ is weaker than the available experimental data.

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O. J. P. Eboli, M. C. Gonzalez-Garcia, S. F. Novaes. 1998-11-18. Indirect Constraints on the Triple Gauge Boson Couplings from $Z \to b \bar{b}$ Partial Width: An Update. https://doi.org/10.1016/s0217-7323(00)00002-5

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