Testing the Majorana Nature of Gluinos and Neutralinos

TL;DR

This paper investigates how the Majorana or Dirac nature of gluinos and neutralinos affects their production and decay signatures at colliders, providing a framework to distinguish between these possibilities.

Contribution

It introduces a framework extending MSSM to N=2 supersymmetry to analyze the impact of Majorana versus Dirac particles on collider observables.

Findings

Like-sign dilepton production is sensitive to the particle's Majorana or Dirac nature.

The framework allows comparison of predictions for Majorana and Dirac scenarios.

Results inform strategies to identify the nature of supersymmetric particles at colliders.

Abstract

Gluinos and neutralinos, supersymmetric partners of gluons and neutral electroweak gauge and Higgs bosons, are Majorana particles in the Minimal Supersymmetric Standard Model [MSSM]. Decays of such self-conjugate particles generate charge symmetric ensembles of final states. Moreover, production channels of supersymmetric particles at colliders are characteristically affected by the Majorana nature of particles exchanged in the production processes. The sensitivity to the Majorana character of the particles can be quantified by comparing the predictions with Dirac exchange mechanisms. A consistent framework for introducing gluino and neutralino Dirac fields can be designed by extending the N=1 supersymmetry of the MSSM to N=2 in the gauge sector. We examine to which extent like-sign dilepton production in the processes q q -> ~q ~q and e- e- -> ~e- ~e- is affected by the exchange of either Majorana or Dirac gluinos and neutralinos, respectively, at the Large Hadron Collider (LHC) and in the prospective e- e- mode of a lepton linear collider.