Search for Physics Beyond the Standard Model Using Multilepton Signatures in pp Collisions at sqrt(s)=7 TeV

TL;DR

This study searches for signs of physics beyond the Standard Model by analyzing multilepton events in proton-proton collisions at 7 TeV, using CMS data to set new constraints on supersymmetry.

Contribution

It introduces a novel analysis of multilepton signatures in early LHC data to probe unexplored supersymmetric parameter regions.

Findings

No significant excess over background observed.

Constraints placed on supersymmetric models.

Methodology reduces reliance on simulation for background estimation.

Abstract

A search for physics beyond the standard model in events with at least three leptons and any number of jets is presented. The data sample corresponds to 35 inverse picobarns of integrated luminosity in pp collisions at sqrt(s) = 7 TeV collected by the CMS experiment at the LHC. A number of exclusive multileptonic channels are investigated and standard model backgrounds are suppressed by requiring sufficient missing transverse energy, invariant mass inconsistent with that of the Z boson, or high jet activity. Control samples in data are used to ascertain the robustness of background evaluation techniques and to minimise the reliance on simulation. The observations are consistent with background expectations. These results constrain previously unexplored regions of supersymmetric parameter space.