D0 Silicon Microstrip Tracker for Run Iia

One main improvement included in the D0 detector upgrade 1 for Run IIa is its central tracking system as shown in Fig. 1. It includes a 2 T superconducting solenoid, a Central scintillating Fiber Tracker (CFT) and the SMT. The SMT design is driven by two classes of events. Barrels and central disks cover the ∼ 25 cm RMS long luminous region for high pT central physics (|η| < 1.5). Forward disks are implemented mainly to study b-physics in the forward region down to pseudo-rapidities of 3. The SMT is comprised of 6 barrels, each barrel mated on one of its ends to an F-disk, 2 stacks of 3 F-disks (end disks modules) and 4 H-disks (see Fig. 1). The barrels are 12 cm long and have 72 ladders arranged in 4 layers (12,12,24,24), each layer having 2 staggered and overlaping sub-layers (see Fig. 2). The 2 outer barrels have single sided (SS) and double sided 2◦ stereo (DS) ladders. The 4 inner barrels have double sided double metal (DSDM) 90◦ stereo and double sided