Supersymmetry at High Luminosity LHC

TL;DR

This paper reviews supersymmetry's theoretical motivation, current experimental constraints, and prospects for detection at the High Luminosity LHC, emphasizing naturalness and string landscape considerations.

Contribution

It provides a comprehensive analysis of SUSY naturalness, dark matter constraints, and updated HL-LHC projections within the string landscape framework.

Findings

Natural SUSY models can accommodate a 125 GeV Higgs.

HL-LHC will probe key SUSY particles like higgsinos and stops.

String landscape favors large soft terms with a weak scale near observed value.

Abstract

Weak-scale supersymmetry (SUSY) is well motivated as a technically natural solution to the gauge hierarchy problem. LHC limits on superpartners, however, have sharpened the Little Hierarchy problem, raising the question of why $m_{weak} \ll m_{soft}$. We review current collider and dark matter constraints and their implications for leading SUSY-breaking scenarios. Electroweak naturalness is revisited using a weak-scale measure that avoids ambiguities associated with high-scale fine-tuning. Also, within the string landscape, soft terms are statistically favored to be large, while anthropic selection enforces a weak scale near the observed value. This framework often termed \emph{stringy naturalness} -- naturally accommodates $m_h \simeq 125$ GeV while placing sparticles above current LHC limits. Updated HL-LHC projections for non-universal Higgs mass (NUHM) models -- the most plausible realization consistent with above picture -- show that searches for higgsinos, stops, and heavy Higgs bosons will soon begin to probe the core of the viable parameter space.