LEP status and future plans

At the end of 1992, LEP completed its fourth year of operation, producing more than 28 inverse picobarns of integrated luminosity in each of the four experiments and a total of three million hadronic Z⁰s. For the first time the machine operated for physics with a new high-tune optics producing the smaller transverse emittance eventually needed for future operation at higher energy. As well as gaining valuable experience with this optics the luminosity lifetime could be improved by using wigglers to control the evolution of beam emittance during a run. In addition, the so-called 8-bunch “pretzel” scheme was commissioned, allowing the number of bunches per beam to be increased from four to eight rewards the end of the year. Present performance limitations are discussed and future plans for increasing both the energy and luminosity are described