Neutralino dark matter confronted by the LHC constraints on Electroweak SUSY signals

TL;DR

This paper examines how LHC constraints on electroweak supersymmetric particles impact neutralino dark matter models, highlighting the significance of electroweak sparticles in dark matter physics and collider signals, and analyzing future search prospects.

Contribution

It provides a detailed analysis of LHC constraints on electroweak sparticles in the MSSM and explores how these constraints affect dark matter relic density and future collider search strategies.

Findings

LHC data significantly constrains MSSM parameter space compatible with dark matter.

Gluino mass limits can be relaxed by up to 25% in certain scenarios.

Multi-lepton plus jets signals can discriminate between different dark matter production mechanisms.

Abstract

The supersymmetric particles (sparticles) belonging exclusively to the electroweak sector of the minimal supersymmetric standard model (MSSM) may hold the key to the observed dark matter relic density in the universe even if all strongly interacting sparticles are very heavy. The importance of the light EW sparticles in DM physics and in producing spectacular collider signals is emphasized. It is shown that even the preliminary data on the direct searches of these sparticles at the LHC, significantly constrain the parameter space of the MSSM compatible with the observed relic density and provide useful hints about the future search prospects. If in addition to the electroweak sparticles the gluinos are also within the reach of the LHC experiments, then the gluino mass limits in the light slepton scenario obtained via the canonical jets + $\met$ channel may be relaxed by as much as 25 $%$ compared to the existing limits. But the corresponding same sign dilepton (SSD) + jets + $\met$ signal will yield enhanced limits competitive with the strongest limits currently available. This is illustrated with the help of benchmark scenarios at the generator level using PYTHIA. If the gluinos are just beyond the current reach of the LHC, then the generic n-lepton + m-jets + missing energy signal may discriminate between different DM producing mechanisms by comparing the signals corresponding to different values of n. This is illustrated by simulating the signals for n = 0 and n = 2 (the SSD signal).