Summary

In the CERN pi complex, antiprotons for collisions with protons or for direct use in experimental targets are provided over a T-ery wide energy range, namely: pp collisions at & = 540 GeV in the SPS, pp collisions at /? = 52 GeV in the ISR, 5's down to a kinetic energy of 5 MeV from LEAR. This report gives an account of the experience gained so far, mainly in 1982, in actual physics runs in SPS and ISR, and during the commissioning of LEAR. The main noveity concerns an extended physics run of two months in the SPS, where a peak luminosity of 5.3X10* ' cm- ' s-l was reached and an integrated lumino-sity of 28 nb- ' (or 2.80~10~ ' cm-*) was supplied to the two main experiments UAI and UA2. Another very encouraging result was obtained in LEAR where p beams, extracted from the Antiproton Accumulator at 3.5 GeV/c and decelerated in the PS to 0.6 GeV/c, were successfully injected and captured in LEAR, decelerated to 50 MeV kinetic energy and stochas-tically cooled. The first physics run will take place this summer. The ISR have exploited their excellent vacuum and reliability by storing antiprotons for physics runs of up to two weeks. There have been 10 physics runs to date and the peak luminosity achieved was 2.5~10~ ~ cm- ' s-l. SPS pp Collider After some trials at the end of 1981', the first extended physics run took place from October to Decem-ber 1982. Following a start-up with 2 p bunches collid-ing with 1 p bunch, the standard operation of 3 p bunches colliding with 3 p bunches was sustained for a total of almost 600 hours in conjunction with the two main experiments UAl and UA2. A total integrated luminosity of '7, 28 (nb-I) was obtained (see Fig. I). Fig. 1 Table 1 gives a short summary of the results obtain-ed to-date, in comparison with the very ambitious design aims set at the beginning of the project in 19782