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arXiv · hep-ph/9805273

Shifting $R_b$ with $A^b_{FB}$

Darwin Chang·Ernest Ma
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Abstract

Precision measurements at the $Z$ resonance agree well with the standard model. However, there is still a hint of a discrepancy, not so much in $R_b$ by itself (which has received a great deal of attention in the past several years) but in the forward-backward asymmetry $A^b_{FB}$ together with $R_b$. The two are of course correlated. We explore the possibilty that these and other effects are due to the mixing of $b_L$ and $b_R$ with one or more heavy quarks.

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Darwin Chang, Ernest Ma. 1998-05-10. Shifting $R_b$ with $A^b_{FB}$. https://doi.org/10.1103/physrevd.58.097301

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