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arXiv · hep-ph/9512251

The Effects of a Vector-like Doublet as the Fourth Generation to $R_b$

Tadashi Yoshikawa
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Abstract

We study the effects of a vector-like SU(2) doublet quarks as the fourth generation on $R_b$ and $R_c$. By considering the constraint from the experimental data of forward-backward asymmetry, $A_{FB}^b$ and $A_{FB}^c$,as well as FCNC among light quarks, we show that there is an allowed region of parameters for $R_b$ but not for $R_c$.

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Tadashi Yoshikawa. 1995-12-07. The Effects of a Vector-like Doublet as the Fourth Generation to $R_b$. https://doi.org/10.1143/ptp.96.269

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