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arXiv · hep-ph/9501258

$R_b$ in supergravity models

X. Wang·J. Lopez·D. Nanopoulos
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Abstract

We compute the supersymmetric contribution to $R_{b}\equiv Γ(Z\to b{\bar b})/Γ(Z\to {\rm hadrons})$ in a variety of supergravity models. We find $R^{\rm susy}_b\lsim0.0004$, which does not shift significantly the Standard Model prediction ($R^{\rm SM}_b=0.2162$ for $m_t=160\GeV$). An improvement in experimental precision by a factor of four would be required to be sensitive to such an effect.

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X. Wang, J. Lopez, D. Nanopoulos. 1995-01-10. $R_b$ in supergravity models. https://arxiv.org/abs/hep-ph/9501258

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