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arXiv · hep-ph/9210235

Uncertainties in Coupling Constant Unification

Paul Langacker·Nir Polonsky
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Abstract

The status of coupling constant unification in the standard model and its supersymmetric extension are discussed. Uncertainties associated with the input coupling constants, $m_{t}$, threshold corrections at the low and high scales, and possible nonrenormalizable operators are parametrized and estimated. A simple parametrization of a general supersymmetric new particle spectrum is given. It is shown that an effective scale $M_{SUSY}$ can be defined, but for a realistic spectrum it may differ considerably from the typical new particle masses. The implications of the lower (higher) values of $α_{s}(M_{Z})$ suggested by low-energy ($Z$-pole) experiments are discussed.

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Paul Langacker, Nir Polonsky. 1992-10-14. Uncertainties in Coupling Constant Unification. https://doi.org/10.1103/physrevd.47.4028

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