SPS - the Super Proton Synchrotron

The Super Proton Synchrotron is the second largest machine in CERN’s accelerator complex. Measuring nearly 7 km in circumference, it takes particles from the PS and accelerates them to provide beams for the Large Hadron Collider, the COMPASS experiment and the CNGS project.

When it switched on in 1976, the SPS became the workhorse of CERN’s particle physics programme. Research using SPS beams has probed the inner structure of protons, investigated nature’s preference for matter over antimatter, looked for matter as it might have been in the first instants of the Universe and searched for exotic forms of matter. A major highlight came in 1983 with the Nobel-prize-winning discovery of W and Z particles made with the SPS running as a proton-antiproton collider.

The SPS has 1317 conventional (room temperature) electromagnets, including 744 dipoles to bend the beams round the ring, and it operates at up to 450 GeV. It has handled many different kinds of particles – sulphur and oxygen nuclei, electrons, positrons, protons and antiprotons.