The OPAL Silicon Microvertex Detector

The silicon microvertex detector precisely locates the point where a particle passed through it. The detector is made up of a series of 3 cm by 6 cm silicon wafers processed by conventional integrated circuit manufacturing techniques. Each detector is about a third of a millimeter thick.

When a charged particle passes through such a piece of silicon, electrons and holes are liberated, and are sucked into strips running along each wafer. By reading out the charge collected on each strip, the position of the passing particle can be reconstructed. Because the strips run right along one wafer, this method can only be used to reconstruct one coordinate. A second coordinate is reconstructed using a second detector with strips at right angles to the first.

See also

OPAL tracking detectors

The central vertex detector