Analysis and Interpretation of Test Beam Data
This chapter describes some of the many pitfalls that may be encountered when developing the calorimeter system for a particle physics experiment. Several of the examples chosen for this chapter are based on the author’s own experience. Typically, the performance of a new calorimeter is tested in a particle beam provided by an accelerator. The potential pitfalls encountered in correctly assessing this performance both concern the analysis and the interpretation of the data collected in such tests. The analysis should be carried out with unbiased event samples. Several consequences of violating this principle are illustrated with practical examples. For the interpretation of the results, it is very important to realize that the conditions in a testbeam are fundamentally different than in practice. This has consequences for the meaning of the term “energy resolution”. It is shown that the way in which the results of beam tests are quoted may create a misleading impression of the quality of the tested instrument.