Status of the ELENA Magnet System

ELENA, the Extra Low ENergy Antiproton ring, will be a CERN facility with the purpose to deliver antiprotons at lowest energies aiming to enhance the study of antimat-ter. It will be a hexagonal shaped ring with a circumfer-ence of about 30 m decelerating antiprotons from energies of 5.3 MeV to 100 keV. Due to the extra-low beam rigidi-ty the design of the magnet system is especially challeng-ing because even small fields, for example arising from residual magnetization and hysteresis, will have a major impact both on the beam trajectory and beam dynamics. In this paper the design approach for such an extra-low beam rigidity magnet system is presented. The main chal-lenges are outlined and solutions for the design of the magnet system are discussed.