Search for new physics in events with opposite-sign leptons, jets, and missing transverse energy in pp collisions at sqrt(s) = 7 TeV

TL;DR

This paper reports a search for new physics beyond the standard model in LHC data with opposite-sign leptons, jets, and missing energy, finding no excess but setting limits on supersymmetric models.

Contribution

It introduces two complementary search strategies for BSM physics in dilepton events and provides constraints on supersymmetric parameter space.

Findings

No excess events observed over standard model predictions.

Set upper limits on BSM contributions in the analyzed signal regions.

Excluded regions of the parameter space in the constrained MSSM.

Abstract

A search is presented for physics beyond the standard model (BSM) in final states with a pair of opposite-sign isolated leptons accompanied by jets and missing transverse energy. The search uses LHC data recorded at a center-of-mass energy sqrt(s) = 7 TeV with the CMS detector, corresponding to an integrated luminosity of approximately 5 inverse femtobarns. Two complementary search strategies are employed. The first probes models with a specific dilepton production mechanism that leads to a characteristic kinematic edge in the dilepton mass distribution. The second strategy probes models of dilepton production with heavy, colored objects that decay to final states including invisible particles, leading to very large hadronic activity and missing transverse energy. No evidence for an event yield in excess of the standard model expectations is found. Upper limits on the BSM contributions to the signal regions are deduced from the results, which are used to exclude a region of the parameter space of the constrained minimal supersymmetric extension of the standard model. Additional information related to detector efficiencies and response is provided to allow testing specific models of BSM physics not considered in this paper.