Precision measurement of cosmic-ray antiproton spectrum

The energy spectrum of cosmic-ray antiprotons ((p) over bar's) has been mea sured in the range 0.18-3.56 GeV, based on 458 (p) over bar's collected by BESS in a recent solar-minimum period. We have detected for the first time a characteristic peak at 2 GeV of (p) over bar's originating from cosmic-ra y interactions with the interstellar gas. The peak spectrum is reproduced b y theoretical calculations, implying that the propagation models are basica lly correct and that different cosmic-ray species undergo a universal propa gation. Future BESS data with still higher statistics will allow us to stud y the solar modulation and the propagation in detail and to search for prim ary (p) over bar components.