The Front End Electronics of the LHCb Straw Tube Tracker

The LHCb experiment is a single-arm spectrometer, designed to study B-hadron decays at the Large Hadron Collider (LHC). It is crucial to accurately and efficiently track the charged decay products with the Outer Tracker straw tube detector, in the high-density particle environment of the LHC. The Outer Tracker Front End electronics provide the precise(0.5ns) drift-time measurement, at an average occupancy of 5% and at a 1MHz trigger rate. The tracking procedure requires high-efficiency, while at the same time putting stringent limits on the noise level. The mass production and installation of 450 fully operational Front End boxes is completed. Quality checks have been performed at several stages, at the level of individual boards and at the global level with dedicated test systems mimicking the real detector and capable of simulating all the readout functionalities. An excellent overall threshold uniformity is achieved with low noise levels.