Testbeam studies of production modules of the ATLAS tile calorimeter

Abstract We report test beam studies of 11% of the production ATLAS Tile Calorimetermodules. The modules were equipped with production front-end electronics and all the calibration systems planned for the final detector. The studies used muon, electron and hadronbeams ranging in energy from 3 to 350 GeV. Two independent studiesshowed that the light yield of the calorimeterwas ∼ 70 pe / GeV , exceeding the design goal by 40%. Electron beams provided a calibration of the modules at the electromagnetic energy scale. Over 200 calorimetercells the variation of the response was 2.4%. The linearity with energy was also measured. Muonbeams provided an intercalibration of the response of all calorimetercells. The response to muonsentering in the ATLAS projective geometryshowed an RMS variation of 2.5% for 91 measurements over a range of rapidities and modules. The mean response to hadronsof fixed energy had an RMS variation of 1.4% for the modules and projective angles studied. The response to hadronsnormalized to incident beam energy showed an 8% increase between 10 and 350 GeV, fully consistent with expectations for a noncompensating calorimeter. The measured energy resolution for hadronsof σ / E = 52.9 % / E ⊕ 5.7 % was also consistent with expectations. Other auxiliary studies were made of saturation recovery of the readout system, the time resolution of the calorimeterand the performance of the trigger signals from the calorimeter.