Performance
Figure of merit:  N0=42/cm (=expected)
Number of photons for =1 particles: 33
Single photon resolution:
 s0=0.8 mrad for finer granularity region (R5900-M16 tubes)
 s0=1.0 mrad for coarser granularity region (R5900-M4 tubes)
Well separated
particle bands