Reanalysis of the Response of 1995 ATLAS TileCal Prototype Modules

Test beam data taken in 1995 with a stack of 5 Tile Calorimeter protoype modules were reanalysed in order to compare the response to pions - in particular, the $\pi/e$ ratio - to that of production modules tested in 2002. Attention was devoted to the following aspects: (1) electron/pion separation in electron runs; (2) response to electrons and its linearity, to establish the elecromagnetic (EM) response scale; (3) selection of hadron runs with no electron contamination; (4) careful inspection of hadron data for spurious effects, and their correction; (5) cell intercalibration with a procedure that preserves the EM scale; (6) correction for the proton fraction in positive particle runs. The final $\pi/e$ ratio, obtained in the energy range of 20 GeV to 300 GeV, is in good agreement with the results from the 2002 data. The increase of $\pi/e$ over the common energy range of 20 to 180 GeV is 7.1% ± 0.4% in the 1995 data vs. 6.6% in 2002 data. The scale of $\pi/e$ in 1995 is about 2% higher than in 2002, well with the error on the EM scale.