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arXiv · 1103.2506

The Study of the contribution of the LHT model to $Zb\bar{b}$ coupling

Bingfang Yang·Xuelei Wang·Jinzhong Han
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Abstract

In the framework of the Littlest Higgs Model with T-parity (LHT), we study the contributions of the new particles to $Zb\bar{b}$ couplings at one-loop level. Based on these results, we further study the branching ratio $R_{b}$ and the unpolarized forward-backward asymmetry ${A_{FB}^{b}}$. We find that the correction of the new particles to $Zb\bar{b}$ couplings is mainly on the left-handed coupling and has small part of the parameter space to alleviate the deviation between theoretical predictions and experimental values. The precision measurement value of $R_{b}$ can give severe constraints on the relevant parameters. The constraints from the precision measurement value of ${A_{FB}^{b}}$ are very weak.

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Bingfang Yang, Xuelei Wang, Jinzhong Han. 2011-03-13. The Study of the contribution of the LHT model to $Zb\bar{b}$ coupling. https://doi.org/10.1016/j.nuclphysb.2011.01.017

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