Experiments at ALPHA

Different Experiments at ALPHA

It is important, that we continuously work on improving our hardware and software, so that we can do the precise measurements that we want and leave space for improvement for the future. These are the different generations of experimental Hardware till now and some of our projects that are near in the future.

Experimental Hardware

Icon of ALPHA1


ALPHA 1 (2005– 2012)

Physics: First trapped antihydrogen. First quantum transitions (hyperfine).

Hardware: Octupole based minimum-B field Ioffe-Prittchard trap for neutral atoms superposed on Penning-Malmberg trap for antihydrogen synthesis.


Icon of ALPHA 2


ALPHA 2 (2012 - present)

Physics: First laser spectroscopy. First laser-cooling.

Hardware: Catching trap introduced to split functionality away from antihydrogen region to improve mechanical access (for e.g. lasers).

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ALPHA Beamline (2018 - present)

A separate system that connects ALPHA 2/3, ALPHA-g and the Positron Accumulator to allow the accumulator to feed positrons to both ALPHA 2/3 and ALPHA-g as well as allow for antiprotons to be transported to ALPHA-g.

Icon of ALPHA3


ALPHA 3 (2021 - present)

Aim: Hydrogen precision in antihydrogen spectroscopy. First observation of photons from antihydrogen. Improved antihydrogen trapping & stacking. Observation of additional optical transitions (e.g. 4s->2s) in antihydrogen

Hardware: Upgrade with fluorescence detection for 121nm light as well as visible wavelengths. Will also include detection of 313nm light for laser-cooling and magnetometry with Be+.


Icon of ALPHA-g


ALPHA-g (2021 - present)

Aim: 10% precision on measurement of the inertial to gravitational mass of antihydrogen. 

Hardware: New vertical system of about double the size of ALPHA 2/3. Double Penning-Malmber trap and neutral atom traps. Highly improved precision in construction of magnets to improve (a) homogeneity of fields and (b) knowledge of fields. Super-conductor mass reduced to limit persistent current issues.