Antimatter Gravity Measurements with Cold Antihydrogen: the AEgIS Experiment

Doser, M.; Amsler, C.; Ariga, T.; Bonomi, G.; Braunig, P.; Brusa, R. S.; Cabaret, L.; Caccia, M.; Caravita, R.; Castelli, F.; Cerchiari, G.; Comparat, D.; Consolati, G.; Demetrio, A.; Di Noto, L.; Ereditato, A.; Evans, C.; Ferragut, R.; Fesel, J.; Fontana, A.; Gerber, S.; Giammarchi, M.; Gligorova, A.; Guatieri, F.; Haider, S.; Holmestad, H.; Huse, T.; Kellerbauer, A.; Krasnicky, D.; Lagomarsino, V.; Lansonneur, P.; Lebrun, P.; Malbrunot, C.; Mariazzi, S.; Matveev, V.; Mazzotta, Z.; Nebbia, G.; Nedelec, P.; Oberthaler, M.; Pacifico, N.; Pagano, D.; Penasa, L.; Petracek, V.; Pistillo, C.; Prelz, F.; Prevedelli, M.; Ravelli, L.; Rienaecker, B.; Røhne, O. M.; Rotondi, A.; Sacerdoti, M.; Sandaker, H.; Santoro, R.; Scampoli, P.; Smestad, L.; Sorrentino, F.; Strojek, I. M.; Testera, G.; Tietje, I. C.; Vamosi, S.; Widmann, E.; Yzombard, P.; Zmeskal, J.; Zurlo, N.

doi:10.1142/9789813148505_0005

The AEgIS (Antimatter Experiment: Gravity, Interferometry, Spectroscopy) experiment has the objective of testing the weak equivalence principle for antimatter, by studying the free fall of antihydrogen atoms in the Earth’s gravitational field, as well as carrying out a measurement of the hyperfine splitting of their ground state. A pulsed cold beam of antihydrogen produced by charge exchange between cold positronium (laser excited into a Rydberg state with principal quantum number n ∼ 25-35) and cold antiprotons will be transformed into a horizontal beam through Stark acceleration, whose free fall will be measured by a classical moirée deflectometer. The status of different crucial steps towards this goal is presented.