The Pad Chambers

As was mentioned in section 2.2 the Pad Chambers are pixel-based multi-wire proportional chambers, used in the central arm tracking system. The three layers, PC1, PC2 and PC3, are placed at roughly 2.5 m, 4.2 m and 5 m away from the beam. (There is no PC2 in the east arm.) They cover about 0.7 units in pseudorapidity and $90\grad$ in azimuth in each arm.