The layer 0 inner silicon detector of the D0 experiment

This paper describes the design, fabrication, installation and performance of the new inner layer called Layer 0 (L0) that was inserted in the existing Run IIa silicon micro-strip tracker (SMT) of the D0 experiment at the Fermilab Tevatron p-bar p collider. L0 provides tracking information from two layers of sensors, which are mounted with center lines at a radial distance of 16.1 and 17.6 mm from the beam axis. The sensors and read-out electronics are mounted on a specially designed and fabricated carbon fiber structure that includes cooling for sensor and read-out electronics. The structure has a thin polyimide circuit bonded to it so that the circuit couples electrically to the carbon fiber allowing the support structure to be used both for detector grounding and a low impedance connection between the remotely mounted hybrids and the sensors.