When the LHC is switched on in 2005, its 40 million particle collisions per second will generate unprecedented amounts of data. The CMS tracking detectors contain over 14 million data channels. Petabytes of data every second result, so an initial sweep is made to extract only the potentially interesting events. In the driver modules, data undergoes two stages of processing.
First noise is removed and errors from faulty channels suppressed.
The data can contain two sorts of noise - 'common mode' noise which is random over all channels and 'pedestal noise' characteristic to each channel. To identify the hit data, they are tagged with timing information before being output from the driver module into the remainder of the CMS data acquisition system. Test beam runs at CERN have already proved successful. Come 2005, the first streams of data are assured to flow smoothly from the CMS experiment. For more information please contact Rob Halsall .