OPAL experiment

The detector components were arranged around the beam pipe, in a layered structure like that of an onion.

The silicon microvertex detector and the vertex chamber were used to locate decay vertices of short-lived particles, and to improve the momentum resolution.

[3] The central jet chamber identified particles from how much ionization they caused, and how far they curved in the magnetic field.

They were complemented by so-called "z-chambers" at the outside edge of the jet chamber, to provide precise measurements of the perpendicular coordinates of the tracks.

In LEP's second phase from 1996 to 2000, the collider's collision energy was increased to make pairs of W bosons, and to search for possible new particles and new physics.

OPAL was one of the four large detectors at the Large Electron-Positron collider (1989–2000). The detector was dismantled in 2001 to make way for construction of the Large Hadron Collider (LHC).