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BASE (Baryon Antibaryon Symmetry Experiment) is a multinational collaboration at the Antiproton Decelerator (AD) facility at CERN, Geneva.
The high-precision comparison of basic properties of matter/antimatter counterparts provides stringent tests of charge-parity-time (CPT) invariance of the Standard Model. The BASE collaboration performs high-precision experiments to compare fundamental properties of protons and antiprotons by determination and comparison of their charge-to-mass ratios and magnetic moments (g factors) in Penning traps.
In the past years, BASE improved the measurement precision of the g-factor of the proton and the antiproton several times. A further significant improvement of the measurement accuracy can be achieved by the application of a new sympathetic cooling scheme.

For further information, please visit the BASE website