The AEGIS detection system for gravity measurements

The main scientific goal of the AEGIS experiment (Antimatter Experiment: Gravity, Interferometry, Spectroscopy) is the direct measurement of the Earth's gravitational acceleration g on a beam of cold antihydrogen ((H) over bar). The production of an antihydrogen beam is achieved by a charge exchange reaction between Rydberg positronium and cold antiprotons. The (H) over bar 77 beam will be accelerated LIP to a velocity of a few 100 m/s and the gravitational acceleration will be obtained by measuring the small vertical deflection of the beam (a few tens mu m) using a Moire' deflectometer.