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

The string landscape statistical draw to large scalar soft masses leads to a mixed quasidegeneracy/decoupling solution to the supersymmetry (SUSY) flavor and <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi>C</a:mi><a:mi>P</a:mi></a:math> 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 renormalization group (RG) effects that suppress the corresponding third generation soft masses. This can also lead to substantial parameter space regions that are forbidden by the presence of charge and/or color breaking minima of the scalar potential. We outline the allowed SUSY parameter space for the gravity-mediated three extra-parameter-nonuniversal Higgs model NUHM3. The natural regions with <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:msub><c:mi>m</c:mi><c:mi>h</c:mi></c:msub><c:mo>∼</c:mo><c:mn>125</c:mn><c:mtext> </c:mtext><c:mtext> </c:mtext><c:mi>GeV</c:mi></c:math>, <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" display="inline"><e:msub><e:mi mathvariant="normal">Δ</e:mi><e:mrow><e:mi>EW</e:mi></e:mrow></e:msub><e:mo>≲</e:mo><e:mn>30</e:mn></e:math> and decoupled first/second generation scalar are characterized by rather heavy gluinos and EW gauginos, but with rather small <h:math xmlns:h="http://www.w3.org/1998/Math/MathML" display="inline"><h:mi>μ</h:mi></h:math> 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 charge and/or color breaking minima.