The OPAL Experiment

Information about the Birmingham OPAL group and our physics involvement

The world's highest energy electron-positron collisions were used at LEP-2 to produce pairs of W bosons in the LEP collider at CERN. The mass and properties of the W boson have been studied, together with many detailed analyses of millions of Z particles recorded in earlier data from LEP-1.

All the analysis work done by Birmingham OPAL members has now been completed. We continue to be involved in a review capacity for some final publications.

The current Birmingham OPAL group:

Prof DG Charlton, Dr CM Hawkes, Prof PM Watkins, Dr AT Watson, Dr MF Watson, Dr NK Watson, Dr JA Wilson

At Birmingham, the main physics analysis studies with LEP-2 data were:

  • The properties of hadronic W decays, including colour reconnection (final publication), done in order to improve the measurement of the W mass (final publication)
  • The measurement of the triple gauge coupling of the photon to W's, and of the Z to W's, using events where two W's decay to leptons (final publication)
  • The measurement of the quartic gauge couplings of two photons and two W's or two Z's, using events with two final-state photons and missing momentum (final publication)
  • The measurement of muon and tau pair production at the highest energies of LEP (final publication)

In addition, we built, operated and maintained over the full twelve years of OPAL the muon endcap detectors, along with its associated simulation and reconstruction software.

The production of all OPAL Monte Carlo samples was done by a system (OPAL MCP) developed and managed for many years by Steve O'Neale, a Birmingham physicist.

For more information, please look at:

B'ham OPAL Webweavers Last updated: 11 August 2005