Deceleration of antiprotons from CERN’s ELENA synchrotron and transport of antimatter beams through the GBAR experiment

The GBAR experiment aims to perform the first free-fall experiment with antihydrogen atoms to test the weak equivalence principle with antimatter. In a first step, antihydrogen ions are synthesized through a double charge exchange reaction and then cooled by laser to reach sufficiently low energies to observe the effects of gravity. The synthesis of anti-ions requires a very large number of antiprotons. We report in this manuscript a new electrostatic instrument for decelerating antiproton bunches from 100 keV to a few keV . This new technique aims to avoid losses caused by the use of degrader foils. Simulations based on a genetic algorithm made it possible to establish the most suitable electrostatic configurations. Preliminary tests carried out on a prototype are discussed. The technical characteristics of the deceleration system, particularly those related to UHV vacuum, high voltage and safety, are described. Finally, a secondary optical systems such as a switchyard or injection optics into a Penning trap are studied.