Decoding the gaugino code, naturally, at high-lumi LHC

TL;DR

This paper explores how different gaugino mass paradigms in natural supersymmetry can be distinguished at the high-luminosity LHC through specific collider signatures, linking string landscape considerations to experimental prospects.

Contribution

It performs landscape scans of gaugino mass models and identifies distinct experimental signatures for each paradigm at the LHC.

Findings

Different gaugino mass models occupy distinct regions in parameter space.

Higgsino pair production can be detected via dilepton plus jets plus MET signatures.

Wino pair production can be identified through same-sign diboson events.

Abstract

Natural supersymmetry with light higgsinos is most likely to emerge from the string landscape since the volume of scan parameter space shrinks to tiny volumes for electroweak unnatural models. Rather general arguments favor a landscape selection of soft SUSY breaking terms tilted to large values, but tempered by the atomic principle: that the derived value of the weak scale in each pocket universe lie not too far from its measured value in our universe. But that leaves (at least) three different paradigms for gaugino masses in natural SUSY models: unified (as in nonuniversal Higgs models), anomaly-mediation form (as in natural AMSB) and mirage mediation form (with comparable moduli- and anomaly-mediated contributions). We perform landscape scans for each of these, and show they populate different, but overlapping, positions in m(\ell\bar{\ell}) and m(wino) space. The first of these may be directly measurable at high-lumi LHC via the soft opposite-sign dilepton plus jets plus MET signature arising from higgsino pair production while the second of these could be extracted from direct wino pair production leading to same-sign diboson production.