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arXiv · 1705.07935

Global fits of GUT-scale SUSY models with GAMBIT

Abstract

We present the most comprehensive global fits to date of three supersymmetric models motivated by grand unification: the Constrained Minimal Supersymmetric Standard Model (CMSSM), and its Non-Universal Higgs Mass generalisations NUHM1 and NUHM2. We include likelihoods from a number of direct and indirect dark matter searches, a large collection of electroweak precision and flavour observables, direct searches for supersymmetry at LEP and Runs I and II of the LHC, and constraints from Higgs observables. Our analysis improves on existing results not only in terms of the number of included observables, but also in the level of detail with which we treat them, our sampling techniques for scanning the parameter space, and our treatment of nuisance parameters. We show that stau co-annihilation is now ruled out in the CMSSM at more than 95\% confidence. Stop co-annihilation turns out to be one of the most promising mechanisms for achieving an appropriate relic density of dark matter in all three models, whilst avoiding all other constraints. We find high-likelihood regions of parameter space featuring light stops and charginos, making them potentially detectable in the near future at the LHC. We also show that tonne-scale direct detection will play a largely complementary role, probing large parts of the remaining viable parameter space, including essentially all models with multi-TeV neutralinos.

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The GAMBIT Collaboration, Peter Athron, Csaba Balázs, Torsten Bringmann, Andy Buckley, Marcin Chrząszcz, Jan Conrad, Jonathan M. Cornell, Lars A. Dal, Joakim Edsjö, Ben Farmer, Paul Jackson, Abram Krislock, Anders Kvellestad, Farvah Mahmoudi, Gregory D. Martinez, Antje Putze, Are Raklev, Christopher Rogan, Roberto Ruiz de Austri, Aldo Saavedra, Christopher Savage, Pat Scott, Nicola Serra, Christoph Weniger, Martin White. 2018-10-23. Global fits of GUT-scale SUSY models with GAMBIT. https://doi.org/10.1140/epjc%2Fs10052-017-5167-0

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