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arXiv · hep-ph/9601326

Solutions to the R_b, R_c and alpha_s puzzles by Vector Fermions

Chia-Hung V. Chang·Darwin Chang·Wai-Yee Keung
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Abstract

We propose two minimal extensions of Standard Model, both of which can easily accommodate the recent puzzling observations about the excess in $R_b$, the deficit in $R_c$ and the discrepancy in the low energy and high energy determinations of $α_{s}$. Each model requires three additional heavy vectorial fermions in order to resolve the puzzles. The current phenomenological constraints and the new potential phenomena are also discussed.

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Chia-Hung V. Chang, Darwin Chang, Wai-Yee Keung. 1996-01-24. Solutions to the R_b, R_c and alpha_s puzzles by Vector Fermions. https://doi.org/10.1103/physrevd.54.7051

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