Search for New Physics in the Dijet Mass Distribution using 1 fb^-1 of pp Collision Data at sqrt(s) = 7 TeV collected by the ATLAS Detector

TL;DR

This study analyzes dijet mass distributions from 7 TeV proton-proton collisions to search for new physics, setting exclusion limits on various hypothetical particles without observing any resonance signals.

Contribution

The paper presents the first search for new physics in dijet mass spectra at 7 TeV using 1 fb^-1 of data, establishing new exclusion limits on several models.

Findings

No resonance signals observed in dijet mass spectrum

Excluded excited quarks below 2.99 TeV

Excluded axigluons below 3.32 TeV

Abstract

Invariant mass distributions of jet pairs (dijets) produced in LHC proton-proton collisions at a centre-of-mass energy sqrt(s)=7 TeV have been studied using a data set corresponding to an integrated luminosity of 1.0 fb^-1 recorded in 2011 by ATLAS. Dijet masses up to ~4 TeV are observed in the data, and no evidence of resonance production over background is found. Limits are set at 95% CL for several new physics hypotheses: excited quarks are excluded for masses below 2.99 TeV, axigluons are excluded for masses below 3.32 TeV, and colour octet scalar resonances are excluded for masses below 1.92 TeV.