ATLAS search for new phenomena in dijet mass and angular distributions using pp collisions at sqrt(s)=7 TeV

TL;DR

This paper reports on a search for new phenomena in dijet mass and angular distributions using 7 TeV proton-proton collision data from the ATLAS detector, setting limits on various hypothetical particles and interactions.

Contribution

The study provides the first comprehensive analysis of dijet distributions at 7 TeV, setting exclusion limits on multiple new physics models with no observed deviations.

Findings

No resonance-like features observed in dijet mass spectrum.

Exclusion limits set on excited quarks, scalar octets, heavy W bosons, string resonances, black holes, and contact interactions.

Abstract

Mass and angular distributions of dijets produced in LHC proton-proton collisions at a centre-of-mass energy sqrt(s)=7 TeV have been studied with the ATLAS detector using the full 2011 data set with an integrated luminosity of 4.8/fb. Dijet masses up to 4.0 TeV have been probed. No resonance-like features have been observed in the dijet mass spectrum, and all angular distributions are consistent with the predictions of QCD. Exclusion limits on six hypotheses of new phenomena have been set at 95% CL in terms of mass or energy scale, as appropriate. These hypotheses include excited quarks below 2.83 TeV, colour octet scalars below 1.86 TeV, heavy W bosons below 1.68 TeV, string resonances below 3.61 TeV, quantum black holes with six extra space-time dimensions for quantum gravity scales below 4.11 TeV, and quark contact interactions below a compositeness scale of 7.6 TeV in a destructive interference scenario.