相关论文: Naturalness Constraints in Supersymmetric Theories…
Superpartner masses cannot be arbitrarily heavy if supersymmetric extensions of the standard model explain the stability of the gauge hierarchy. This ancient and hallowed motivation for weak scale supersymmetry is often quoted, yet no…
The data obtained by the LHC collaborations clearly show that supersymmetric models are not realized in nature in a vanilla form and that in particular strongly interacting supersymmetric particles are most likely heavier than expected. An…
We explore unification and natural supersymmetry in a five dimensional extension of the standard model in which the extra dimension may be large, of the order of 1-10 TeV. Power law running generates a TeV scale A_ term allowing for the…
Supersymmetric theories which can allow for a 125 GeV Higgs mass and also solve the naturalness and susy flavor problems now require a fair degree of complexity. Here we consider the simplest possibility for supersymmetry near the weak…
One way to suppress flavor changing neutral currents or CP violating processes in supersymmetry is to make at least some of the first two generations' scalars superheavy (above ~20 TeV). We summarize the motivations and challenges,…
The supersymmetric flavor, CP and Polonyi problems are hints that the fundamental scale of the soft supersymmetry breaking parameters may be above a TeV, in apparent conflict with naturalness. We consider the possibility that multi-TeV…
Influenced by the current trend of experimental data, especially from the LHC, we construct a supersymmetric scenario where a natural dynamics makes the squarks and gluino super-heavy (order 10 TeV) while keeping the sleptons and the weak…
We analyse the fine-tuning constraints arising from absence of superpartners at LEP, without strong universality assumptions. We show that such constraints do not imply that charginos or neutralinos should have been seen at LEP, contrary to…
We demonstrate that natural supersymmetry is readily realized in the framework of SU(4)_c \times SU(2)_L \times SU(2)_R with non-universal gaugino masses. Focusing on ameliorating the little hierarchy problem, we explore the parameter space…
Natural models of supersymmetry with a gravitino LSP provide distinctive signatures at the LHC. For a neutralino NLSP, sparticles can decay to two high energy photons plus missing energy. We use the ATLAS diphoton search with 4.8 fb^{-1} of…
Particle physics models with Natural Supersymmetry are characterized by a superpotential parameter \mu \sim m_h \sim125$ GeV, while third generation squarks have mass <0.5-1.5 TeV. Gluinos should be lighter than several TeV so as not to…
After a general discussion about the quantitative meaning of the naturalness upper bounds on the masses of supersymmetric particles, we compute these bounds in models with gauge-mediated soft terms. We find interesting upper limits on the…
The lightest supersymmetric particles could be higgsinos that have a small mixing with gauginos. If the lightest higgsino-like state makes up some or all of the dark matter with a thermal freezeout density, then its mass must be between…
In light of recent 80-137 $\rm{fb}^{-1}$ results at the LHC Run 2 establishing a lower gluino mass limit of 2.25 TeV, we revisit the supersymmetric GUT model Flipped $SU$(5) with extra vector-like particles, known as $\cal{F}$-$SU$(5), with…
The naturalness of a Higgs boson with a mass near 125 GeV is explored in a variety of weak-scale supersymmetric models. A Higgs mass of this size strongly points towards a non-minimal implementation of supersymmetry. The Minimal…
We consider 4D weak scale theories arising from 5D supersymmetric (SUSY) theories with maximal Scherk-Schwarz breaking at a Kaluza-Klein (KK) scale of several TeV. Many of the problems of conventional SUSY are avoided. Apart from 3rd family…
Experimental bounds on squarks of the first two generations assume their masses to be eightfold degenerate, and consequently constrain them to be heavier than ~ 1.4 TeV when the gluino is lighter than 2.5 TeV. The assumption of squark-mass…
Searches for charginos, neutralinos and sleptons at LEP2 centre-of-mass energies from 130 GeV to 189 GeV have been used to set lower limits on the mass of the Lightest Supersymmetric Particle and other supersymmetric particles within the…
We revisit the minimal supersymmetric SU(5) grand unified theory with three right-handed neutrinos in which universality conditions for soft-supersymmetry breaking parameters are imposed at an input scale above the unification scale. If the…
The lack of evidence for low energy supersymmetry at the LHC implies a supersymmetry scale in excess a TeV. While this is consistent (and even helpful) with a Higgs boson mass at $\approx$ 125 GeV, simple supersymmetric models with scalar…