PERFORMANCE OF THE OPAL JET CHAMBER

The jet chamber of the OPAL experiment at the LEP e+e- collider is designed to measure the direction and the momentum of charged particles as well as the specific energy loss in the chamber gas. The jet chamber has been operated at LEP since August 1989 and has recorded 500000 hadronic decays of the Z0, resulting in a good understanding of the stability and systematics of the chamber. Resolutions obtained in the measurement of particle direction, momentum, and specific energy loss are presented, as well as the corrections and calibration procedures necessary to attain original design goals. A momentum resolution of 6.8% for particles with a momentum of 45 GeV/c and an energy loss resolution of 3-4% over all momenta have been achieved.