The Antiproton Accumulator (AA) was an infrastructure connected to the Proton–Antiproton Collider (SppS) – a modification of the Super Proton Synchrotron (SPS) – at CERN.

[3][4] In the SppS the antiprotons were made to collide with protons, achieving collisions at a center of mass energy of app.

[5] He shared the prize with Simon van der Meer, whose invention of the method of stochastic cooling made large scale production of antiprotons possible for the first time.

[6] The produced antiprotons would have a substantial momentum spread, which was decreased during a 2 s orbit around the AA, using Simon van der Meers method of stochastic cooling.

[12] After the last run of the SppS, in 1991, LEAR remained the sole client of the AAC, and a simpler way to serve low-energy physics was sought.