This quality control guaranteed not only good performance of the final calorimeter in all sections but also provided information of light output and optical uniformity that could already be used in the GEANT simulations.
The crystal tests can be classified in
1) Visual inspection
2) Check
of dimensional tolerances
3) Measurement of the light yield ratio of the two
emission components
4) Optical uniformity determination
5) Light yield
measurement.
(Between steps 3) and 4) the crystals were coated and wrapped.)