The impact of a front cooling plate of aluminium on the energy resolution was studied. The cooling plate was placed in front of the crystals (distance: 3mm) and its thickness was varied between 0mm and 10mm.

The geometry can be seen in the following figures.
Unfortunately the inner cooling plate (inner red ring) was set to a thickness of 10mm instead of 1mm. This worsens the energy resolution for the inner crystals. In the final set-up a thickness of 1mm is foreseen.

Materials: