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5 Additional Information
5.1 Storage
CEMs are comparatively resistant to the repeated aeration of the vacuum chamber. However, when exposed
to air over a longer period of time, the binding of moisture leads to a decrease in gain and therefore to a
reduction of the lifetime.
For this reason, the CEM assemblies are delivered in a sealed container filled with argon. We recommend
not opening the container before the detector is actually required. Alternatively, store the CEMs in argon,
dry air or even better, in vacuum.
Water may lead to a reduction in the work function, resulting in a higher gain. During the burn-in after
having been stored for a longer period of time, the CEMs may pass through a deep valley of gain until
they reach a stable plateau again. This should be considered when setting the applied voltage and the
discriminator threshold.
5.2 Replacement
Note
Contact SURFACE CONCEPT before performing a replacement.
Please contact Surface Concept before performing replacement of any parts. We will provide you with a
detailed step by step description.
