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The readout is 3cm x 3cm squares.
An x-y quarter view of the sid02 tracking detectors can be found at sid02_Calorimeters_QuarterView.eps
Masks and Far Forward Detectors
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All the far forward electromagnetic calorimeters have 3.5mm x 3.5 mm square readout.
An x-y quarter view of the sid02 tracking detectors can be found at sid02_MDI_Cut.eps
For additional details, please see the xml file.