PERFORMANCE OF ATLAS EM MODULES IN TEST BEAM

Abstract

The pre-series (module 0) and series modules (barrel: M10, M13; endcap ECCO, ECC1) of the future electromagnetic barrel and endcap calorimeters' of ATLAS have been tested in electron beams at CERN's H6 (H8) beam line with energies from 10 GeV up to 180 GeV (245 GeV). The construction of these modules is described elsewhere2. The goal of the module 0 tests, performed from 1998 to 2000, was the validation of changes since the previous prototypes built and tested in 1997314, i.e., the use of large electrodes, use of lead sheets with a constant thickness in the endcap, cold electronics (summing and mother boards). In the course of these tests, the design of the summing and mother boards was improved and validated. In addition, the test beam also served to validate the ATLASlike electronics (Front End Board, Calibration Board) which are described elsewhere5. The beam tests of the series modules are part of the quality and acceptance control for ATLAS modules. In the following the module 0 results are final, whereas the series module results are preliminary. The paper is structured as follows: first the test beam setup will be described, followed by a discussion of the signal reconstruction. The modules' response to muons and electrons will be presented and compared to Monte Carlo simulations. The results are summarized in the last section.