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arXiv · hep-ph/9606436

$Zb\bar{b}$ Loop Correction with Charge 2/3 Singlet Quarks

Wei-Shu Hou·Hsien-chung Kao
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Abstract

We calculate the non-universal correction to the $Zb\bar{b}$ vertex in a simple extension of the Standard Model, where a charge $+2/3$ isosinglet quark is added to the standard spectrum. Comparison is made with other solutions to $R_b$ (and $R_c$) that demand particles lighter than $M_W$.

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Wei-Shu Hou, Hsien-chung Kao. 1996-06-26. $Zb\bar{b}$ Loop Correction with Charge 2/3 Singlet Quarks. https://doi.org/10.1016/0370-2693(96)01074-x

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