Impact of the choice of physics list on GEANT4 simulations of hadronic showers in tungsten

The development of pion induced showers in a large block of matter (tungsten, lead, iron) is simulated for pions from 1 to 50GeV. Two GEANT4 physics lists (QGSP BERT and QGSP BERT HP) are compared. The deposited energy at each step of the simulation is identified as visible, invisible or escaped. It will be shown, that for tungsten in most of the hadronic showers more than 90% of the energy is deposited visibly if QGSP BERT is used. This fraction drops to only 60% for QGSP BERT HP. The latter fraction is similar to lead, even when QGSP BERT is used for the simulation. The impact of this behaviour on the energy resolution of a sampling calorimeter with scintillator as active material is shown. Although more energy is deposited visibly for QGSP BERT than for QGSP BERT HP, the reconstructed energy resolution is about 5 to 10% percent better for the latter.