Search for squarks and gluinos in events with isolated leptons, jets and missing transverse momentum at $\sqrt{s}=8$ TeV with the ATLAS detector

TL;DR

This paper reports a search for supersymmetric particles like squarks and gluinos in proton-proton collisions at 8 TeV using the ATLAS detector, finding no excess but setting new exclusion limits on their masses.

Contribution

The study provides the first comprehensive limits on squark and gluino masses at 8 TeV, extending previous bounds and testing minimal supersymmetric models with ATLAS data.

Findings

No significant excess observed over Standard Model predictions.

Excluded gluino masses up to 1.32 TeV and squark masses up to 840 GeV.

Set limits on parameters of minimal universal extra dimensions model.

Abstract

The results of a search for supersymmetry in final states containing at least one isolated lepton (electron or muon), jets and large missing transverse momentum with the ATLAS detector at the Large Hadron Collider (LHC) are reported. The search is based on proton-proton collision data at a centre-of-mass energy $\sqrt{s} = 8$ TeV collected in 2012, corresponding to an integrated luminosity of 20 fb$^{-1}$. No significant excess above the Standard Model expectation is observed. Limits are set on the parameters of a minimal universal extra dimensions model, excluding a compactification radius of $1/R_c=950$ GeV for a cut-off scale times radius ($\Lambda R_c$) of approximately 30, as well as on sparticle masses for various supersymmetric models. Depending on the model, the search excludes gluino masses up to 1.32 TeV and squark masses up to 840 GeV.