Dependence of the Jet Energy Scale on the Particle Content of Hadronic Jets in the ATLAS Detector Simulation

The dependence of the ATLAS jet energy measurement on the modelling in Monte Carlo simulations of the particle types and spectra within jets is investigated. It is found that the hadronic jet response, i.e. the ratio of the reconstructed jet energy to the true jet energy, varies by about 1-2% depending on the hadronisation model used in the simulation. This effect is mainly due to differences in the average energy carried by kaons and baryons in the jet. Model differences observed for jets initiated by quarks or gluons produced in the hard scattering process are dominated by the differences in these hadron energy fractions indicating that measurements of the hadron content of jets and improved tuning of hadronization models can result in an improvement in the precision of the knowledge of the ATLAS jet energy scale.