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$α_s(M_Z^2)$ and $R_b$ discrepancy with nonuniversal interactions

Jae Kwan Kim·Yeong Gyun Kim·Jae Sik Lee·Kang Young Lee
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Abstract

We implement global fits to LEP data with the \non interactions. Consistent $R_b$ with experimental value and consistent $\as(M_Z^2)$ with that from low energy experiments are obtained. We also find that the $\xx$ is better than the Standard Model. And we argue that other kinds of new physics are needed to explain the difference between the values of $\as(M_Z^2)$ from low energy experiments and from the 3-jet ratio.

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Jae Kwan Kim, Yeong Gyun Kim, Jae Sik Lee, Kang Young Lee. 1995-09-18. $α_s(M_Z^2)$ and $R_b$ discrepancy with nonuniversal interactions. https://doi.org/10.1103/physrevd.53.1712

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