Jet energy scale setting with "photon+Jet" events at LHC energies. Selection of events with a clean "photon+Jet" topology and photon Pt - jet Pt disbalance

TL;DR

This paper demonstrates that limiting the transverse momentum activity outside the photon+jet system improves the balance between photon and jet transverse momenta, aiding jet energy calibration at LHC.

Contribution

It introduces a method to select photon+jet events with reduced Pt disbalance by restricting activity outside the system for better calibration accuracy.

Findings

Pt activity limitation reduces photon-jet Pt disbalance

Restricting cluster Pt and Pt^out improves event selection

Method enables effective jet energy scale setting at LHC

Abstract

It is shown in the paper that Pt activity limitation (modulus of the vector sum) of all particle beyond "photon+Jet" system Pt^out leads to the noticeable photon Pt - jet Pt disbalance decreasing. On a simultaneous restriction of the cluster Pt and Pt^out from above it is possible to reach an acceptable balance between photon Pt - jet Pt with a sufficient number of the photon Pt - jet Pt events for the jet energy scale setting and hadron calorimeter calibratiom of the CMS detector at LHC.