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arXiv · hep-ph/9807231

Alpha_s and Gauge Coupling Unification in Flipped SU(5) Models with Gauge-Mediated Supersymmetry Breaking

K. T. Mahanthappa·Sechul Oh
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Abstract

We examine gauge coupling unification and prediction for $α_s (M_Z)$ in minimal flipped SU(5) with gauge-mediated supersymmetry breaking. We include threshold corrections at weak scale, messenger scale and unification scale, and explicitly show that in this model there can be either \emph{one-step} or \emph{two-step} gauge coupling unification, depending on unification-scale threshold corrections. The experimental value of $α_s (M_Z)$ constrains heavy particle masses in one-step unification. In the case of two-step unification, we examine the prediction for $α_s (M_Z)$ with two-loop, light, messenger and heavy threshold corrections, and find it to be compatible with the updated experimental data.

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K. T. Mahanthappa, Sechul Oh. 1998-09-14. Alpha_s and Gauge Coupling Unification in Flipped SU(5) Models with Gauge-Mediated Supersymmetry Breaking. https://doi.org/10.1016/s0370-2693(98)01171-x

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