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arXiv · hep-ph/9505268

The $R_b$ Excess at LEP: Clue to New Physics at the TEVATRON?

Ernest Ma·Daniel Ng
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Abstract

If the $R_b$ excess at LEP is real, then any explanation in terms of renormalizable loop corrections leads to important new decay modes of the $t$ quark and suppresses the $t \to bW$ branching ratio. In the two-Higgs-doublet model, the branching ratio of $Z \to b \bar b$ + a light boson which decays itself predominantly into $b \bar b$ is at least of order $10^{-4}$.

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Ernest Ma, Daniel Ng. 1995-05-09. The $R_b$ Excess at LEP: Clue to New Physics at the TEVATRON?. https://doi.org/10.1063/1.49317

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