General antiparticle spectrometer (GAPS) is a planned experiment that will use a high-altitude balloon flying in Antarctica to look for antideuteron particles from outer space cosmic rays,[1] in an effort to search for dark matter.
Anti-deuterons could perhaps be produced by the annihilation of hypothetical weakly interacting massive particles (WIMPs).
[2] The goal of the GAPS experiment is to capture anti-deuterons in a target material, to form an exotic atom in an excited state.
The exotic atom would quickly decay, producing detectable X-rays energies with pion signature from nuclear annihilation.
The first high-altitude balloon test was done in June 2012 with six Si(Li) detectors.