Search for Diphoton Events with Large Missing Transverse Energy with 36 pb^-1 of 7 TeV Proton-Proton Collision Data with the ATLAS Detector

TL;DR

This paper reports a search for diphoton events with large missing transverse energy using 7 TeV proton-proton collision data, setting new limits on supersymmetry and extra dimension models with no observed excess.

Contribution

First search for diphoton events with large missing energy at 7 TeV, establishing the most stringent limits on GGM supersymmetry and universal extra dimensions models.

Findings

No excess observed over Standard Model predictions.

Set lower limits of 560 GeV on gluino mass in GGM.

Set lower limit of 961 GeV on UED compactification radius R.

Abstract

Making use of 36 pb^-1 of proton-proton collision data at sqrt{s} = 7 TeV, the ATLAS Collaboration has performed a search for diphoton events with large missing transverse energy. Observing no excess of events above the Standard Model prediction, a 95% Confidence Level (CL) upper limit is set on the cross section for new physics of sigma < 0.38 - 0.65 pb in the context of a generalised model of gauge mediated supersymmetry breaking (GGM) with a bino-like lightest neutralino, and of sigma < 0.18 - 0.23 pb in the context of a specific model with one universal extra dimension (UED). A 95 % CL lower limit of 560 GeV, for bino masses above 50 GeV, is set on the GGM gluino mass, while a lower limit of 1/R > 961 GeV is set on the UED compactification radius R. These limits provide the most stringent tests of these models to date.