Low Energy Antiproton Ring

LEAR is a multipurpose storage ring located in the South Hall of the Proton Synchrotron (PS), with a circumference of 78.5 m. Four straight sections are alternated with compact 90° bending magnets, along with eight quadrupole doublets. The straight sections each consist of an 8m long section, where equipment such as apparatus for internal beams and electron cooling can be stored, and two short sections of 1m. The vacuum system used for LEAR is designed for baking at 300 °C. The bunch was transferred to LEAR where it could be decelerated to a minimum 100 MeV/c or accelerated to generally 1000 MeV/c. Using cooling, high quality beams at low energies and low emittances could be produced. == Results ==

There was a total of 27 experiments performed during LEAR's 14 years of running. Several meson spectroscopy experiments were set up at LEAR to analyse the rare meson resonances produced in nucleon-antiproton annilhilation. These included the Crystal Barrel, OBELIX and JETSET experiments. The mass difference between the proton and antiproton was also studied at LEAR with an accuracy in 1 part in 1010. == Conversion to LEIR ==

In 1996, LEAR was converted into the Low Energy Ion Ring, which has since been used in the lead ion injection process for the Large Hadron Collider. Low energy antiproton research continues at CERN using the Antiproton Decelerator. It was built as a successor for LEAR and started operation in 2000. == References ==