An AMS prototype designated AMS-01, a simplified version of the detector, was built by the international consortium under Ting's direction and flown into space aboard the Space Shuttle Discovery on STS-91 in June 1998.
By not detecting any  antihelium the AMS-01 established an upper limit of 1.1×10⁻⁶ for the antihelium to helium flux ratio and proved that the detector concept worked in space.
This shuttle mission was the last shuttle flight to the Mir Space Station.
An AMS prototype designated AMS-01, a simplified version of the detector, was built by the international consortium under Ting's direction and flown into space aboard the Space Shuttle Discovery on STS-91 in June 1998. By not detecting any  antihelium the AMS-01 established an upper limit of 1.1×10⁻⁶ for the antihelium to helium flux ratio and proved that the detector concept worked in space. This shuttle mission was the last shuttle flight to the Mir Space Station.
Alpha Magnetic Spectrometer