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arXiv · hep-ph/0502095

Supersymmetry and precision data after LEP2

Guido Marandella·Christian Schappacher·Alessandro Strumia
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Abstract

We study one loop supersymmetric corrections to precision observables. Adding LEP2 e ebar --> f fbar cross sections to the data-set removes previous hints for SUSY and the resulting constraints are in some cases stronger than direct bounds on sparticle masses. We consider specific models: split SUSY, CMSSM, gauge mediation, anomaly and radion mediation. Beyond performing a complete one-loop analysis, we also develop a simple approximation, based on the Shat, That, W, Y `universal' parameters. SUSY corrections give W,Y > 0 and mainly depend on the left-handed slepton and squark masses, on M_2 and on mu.

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Guido Marandella, Christian Schappacher, Alessandro Strumia. 2005-02-10. Supersymmetry and precision data after LEP2. https://doi.org/10.1016/j.nuclphysb.2005.03.001

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