Living dangerously with decoupled first/second generation scalars: SUSY prospects at the LHC

TL;DR

This paper explores a SUSY scenario with very heavy first/second generation scalars that naturally suppress third generation masses, affecting LHC search prospects and addressing flavor and CP problems.

Contribution

It analyzes the parameter space of a non-universal Higgs model with decoupled scalars, highlighting natural regions consistent with Higgs mass and LHC constraints.

Findings

Heavy first/second generation scalars suppress third generation soft masses via two-loop RG effects.

Natural SUSY regions feature heavy gluinos and electroweak gauginos with small ermi.

Parameter space with light scalars is excluded by charge and/or color breaking minima.

Abstract

The string landscape statistical draw to large scalar soft masses leads to a mixed quasi-degeneracy/decoupling solution to the SUSY flavor and CP problems where first/second generation matter scalars lie in the 20-40 TeV range. With increasing first/second generation scalars, SUSY models actually become more natural due to two-loop RG effects which suppress the corresponding third generation soft masses. This can also lead to substantial parameter space regions which are forbidden by the presence of charge and/or color breaking (CCB) minima of the scalar potential. We outline the allowed SUSY parameter space for the gravity-mediated three extra-parameter-non-universal Higgs model NUHM3. The natural regions with m_h~ 125 GeV, \Delta_{EW}<~ 30 and decoupled first/second generation scalar are characterized by rather heavy gluinos and EW gauginos, but with rather small \mu and top-squarks not far beyond LHC Run 2 limits. This scenario also explains why SUSY has so far eluded discovery at LHC in that the parameter space with small scalar and gaugino masses is all excluded by the presence of CCB minima.