Endcap Calorimeter Prototype 
This is a closeup view of trigger counter B and C and the calorimeter prototype used during T-438. The 2.54 cm diameter hole in counter C was aligned with the beam. The beam enters the calorimeter at approximately the black mark on the drawing attached to the detector box. The beam enters high on "tower 7" to compensate for the projective geometry of the calorimeter tower. The lines on the drawing indicate the approximate path for the wave-length shifting optical fibers used to collect scintillation light. The extra fiber length is to compensate for the varying ratio of the length of the sigma groove to the enclosed area for different tiles that form the projective calorimeter tower.   
Slide 6 of 9