Electromagnetic Energy Calibration of the TILECAL Modules with the Flat Filter Method (July 2002 Test Beam Data)

The constructed ATLAS detector at the LHC will have the great physics discovery potential, in particular in the detection of a heavy Higgs boson. Calorimeters will play a crucial role in it. The important question of calorimetry is the calibration in the electromagnetic energy scale. With the aim of establishing of this scale and understanding of performance of the ATLAS Tile hadronic calorimeter to electrons 12\% of modules have been exposed in electron beams with various energies by three possible ways: cell-scan at $\theta =20^o$ at the centers of the front face cells, $\eta$-scan and tilerow scan at $\theta = 90^o$ for the module side cells. Our work is devoted to the determination of the electromagnetic energy calibration constants of the EBM$-$ (ANL-44), EBM$+$ (IFA-42), BM (JINR-55) TILECAL modules at energies E = 10, 20, 50, 100 and 180 GeV and $\theta = 20^o$ and $90^o$ and $\eta$ scans on the basis of the July 2002 testbeam run data using the flat filter method of the PMT signal reconstruction. The obtained average electron calibration constants equal to $\langle R_e \rangle = 1.157\pm0.002$, $RMS = 2.6\pm0.2$\% for $\theta = 20^o$, $\langle R_e \rangle = 1.196\pm0.005$, $RMS = 5.7\pm0.3$\% for $\theta = 90^o$ and $\langle R_e \rangle = 1.143\pm0.005$, $RMS = 3.7\pm0.3$\% for $\eta$- scan. The obtained calibration constants have been included in the TILECAL calibration database and will be used for the energy calibration of all TILECAL modules.