PT Journal
AU ATLAS Collaboration (Adragna, Pea
   Castelo, J
   Castillo Gimenez, V
   Cuenca, C
   Ferrer, A
   Fullana, E
   Gonzalez, V
   Higon-Rodriguez, E
   Poveda, J
   Ruiz, A
   Salvachua, B
   Sanchis, E
   Solans, C
   Torres, J
   Valero, A
   Valls Ferrer, JA
TI Measurement of pion and proton response and longitudinal shower profiles up to 20 nuclear interaction lengths with the ATLAS Tile calorimeter
SO Nuclear Instruments & Methods in Physics Research A
JI Nucl. Instrum. Methods Phys. Res. A
PY 2010
BP 158
EP 181
VL 615
IS 2
DI 10.1016/j.nima.2010.01.037
LA English
DE Calorimeter; Test-beam; ATLAS; Monte Carlo simulation; GEANT4; Hadronic shower development; Pion-proton response; Longitudinal shower profile for hadrons
AB The response of pions and protons in the energy range of 20-180 GeV, produced at CERN's SPS H8 test-beam line in the ATLAS iron-scintillator Tile hadron calorimeter, has been measured. The test-beam configuration allowed the measurement of the longitudinal shower development for pions and protons up to 20 nuclear interaction lengths. It was found that pions penetrate deeper in the calorimeter than protons. However, protons induce showers that are wider laterally to the direction of the impinging particle. Including the measured total energy response, the pion-to-proton energy ratio and the resolution, all observations are consistent with a higher electromagnetic energy fraction in pion-induced showers. The data are compared with GEANT4 simulations using several hadronic physics lists. The measured longitudinal shower profiles are described by an analytical shower parametrization within an accuracy of 5-10%. The amount of energy leaking out behind the calorimeter is determined and parametrized as a function of the beam energy and the calorimeter depth. This allows for a leakage correction of test-beam results in the standard projective geometry.
ER