Search for supersymmetry in events with a lepton, a photon, and large missing transverse energy in pp collisions at sqrt(s) = 7 TeV

TL;DR

This paper reports a search for supersymmetry in proton-proton collisions at 7 TeV, focusing on events with a lepton, photon, and missing energy, but finds no evidence of new physics and sets exclusion limits.

Contribution

It introduces a search for gauge-mediated supersymmetry with specific final states and provides new exclusion limits on superpartner masses based on LHC data.

Findings

No excess above standard model expectations was observed.

Set 95% confidence level upper limits on cross sections.

Excluded certain ranges of squark, gluino, and wino masses.

Abstract

A search is performed for an excess of events, over the standard model expectations, with a photon, a lepton, and large missing transverse energy in pp collisions at sqrt(s) = 7 TeV. Such events are expected in many new physics models, in particular a supersymmetric theory that is broken via a gauge-mediated mechanism, when the lightest charged and neutral gauginos are mass degenerate. The data sample used in this search corresponds to an integrated luminosity of 35 inverse picobarns collected with the CMS detector at the LHC. No evidence of such an excess above the standard model backgrounds, dominated by W-gamma production, is found. The results are presented as 95% confidence level upper limits on the cross section for a benchmark gauge-mediated scenario, and are then converted into exclusion limits on the squark, gluino, and wino masses.