Radiatively-driven Natural Supersymmetry

Abstract

Within the framework of supersymmetric theories, a question arises: how can the W, Z, and h masses be so low (∼ 100 GeV) when the superpartner masses are so high (mSUSY > 1−2 TeV)? This is the little hierarchy problem, and can be quantified by studying the fine-tuning of a particular model. Quantifying a model in such a way provides a unique opportunity to give upper bounds on the supersymmetric particle masses. Introduced in this dissertation is the model called Radiatively-driven Natural Supersymmetry, wherein low fine-tuning is achieved while maintaining a light Higgs scalar ≃ 125 GeV. In addition, RNS offers a particle spectrum that evades searches at all current collider experiments, and satisfies cosmological constraints. It is shown that RNS could be discovered with high luminosity at LHC14 in multiple channels, having a soft trilepton + MET signature, a unique same-sign diboson signature accompanied by jets, and gluino cascade decays in the trilepton+jets channel. An International Linear Collider operating at √s = 600 GeV would either discover RNS or rule it out as a feasible model. Dark matter direct and indirect detection experiments also offer a means of discovery, with a 1-ton noble gas detector effectively probing the entirety of RNS parameter space.