The Dijet Mass Spectrum and a Search for Quark Compositeness in bar{p}p Collisions at sqrt{s} = 1.8 TeV

TL;DR

This study measures the dijet mass spectrum at the Fermilab Tevatron to test quantum chromodynamics predictions and searches for signs of quark compositeness, setting limits on new physics models.

Contribution

It provides the first detailed measurement of the inclusive dijet mass spectrum at 1.8 TeV and constrains quark compositeness models with a contact interaction scale below 2.4 TeV.

Findings

QCD predictions agree with measured spectra

No evidence for quark compositeness up to 2.4 TeV

Measured dijet mass spectrum consistent with Standard Model

Abstract

Using the DZero detector at the 1.8 TeV pbarp Fermilab Tevatron collider, we have measured the inclusive dijet mass spectrum in the central pseudorapidity region |eta_jet| < 1.0 for dijet masses greater than 200 Gev/c^2. We have also measured the ratio of spectra sigma(|eta_jet| < 0.5)/sigma(0.5 < |eta_jet| < 1.0). The order alpha_s^3 QCD predictions are in good agreement with the data and we rule out models of quark compositeness with a contact interaction scale < 2.4 TeV at the 95% confidence level.