Validation of Geant4 Physics Using the CMS HCAL Test Beam 2002 Experiment

High energy physics measurements relay to a great extent on the accuracy of physics generators and detector simulations. The size of systematic uncertainties associated with particle discoveries, mass, or cross section measurements is tightly associated with how accurately the simulations describe the actual performance of the detector in measuring physics objects. Physics validation studies of Geant4 using physics lists LHEP-3.6 and QGSP-2.7, and based on HCAL test beam taken in 2002, are presented in this note. The pion energy resolution and response linearity as a function of incident energy derived from the simulations are in good agreement with the data measurement within the large systematics uncertainties in the latter. Below 30GeV, the uncertaintiesin the data are too large to provide information about deviationsof the Monte Carlo model with respect to the data measurements. Tr ansverse and longitudinal shower profiles are also studied in the Monte Carlo, but no data were analyzed. In particular, longitudial segmentation was anavailable in the Test Beam 2002 read out.