Testbeam studies of production modules of the ATLAS Tile Calorimeter

We report test beam studies of {11\,\%} of the production ATLAS Tile Calorimeter modules. 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 hadron beams ranging in energy from 3~GeV to 350~GeV. Two independent studies showed that the light yield of the calorimeter was $\sim 70$~pe/GeV, exceeding the design goal by {40\,\%}. Electron beams provided a calibration of the modules at the electromagnetic energy scale. Over 200~calorimeter cells the variation of the response was {2.4\,\%}. The linearity with energy was also measured. Muon beams provided an intercalibration of the response of all calorimeter cells. The response to muons entering in the ATLAS projective geometry showed an RMS variation of 2.5\,\% for 91~measurements over a range of rapidities and modules. The mean response to hadrons of fixed energy had an RMS variation of {1.4\,\%} for the modules and projective angles studied. The response to hadrons normalized to incident beam energy showed an {8\,\%} increase between 10~GeV and 350~GeV, fully consistent with expectations for a non-compensating calorimeter. The measured energy resolution for hadrons of $\sigma/E = 52.9\,\%/\sqrt{E} \oplus 5.7\,\%$ was also consistent with expectations. Other auxiliary studies were made of saturation recovery of the readout system, the time resolution of the calorimeter an d the performance of the trigger signals from the calorimeter.