Radiation hardness qualification of PbWO4 scintillation crystals for the CMS Electromagnetic Calorimeter

Understand

Ensuring the radiation hardness of PbWO4 crystals was one of the main priorities during the construction of the electromagnetic calorimeter of the CMS experiment at CERN.

• The production on an industrial scale of radiation hard crystals and their certification over a period of several years represented a difficult challenge both for CMS and for the crystal suppliers.
• The present article reviews the related scientific and technological problems encountered.