Astrophysical implications of cosmic-ray antiprotons

The production and propagation of secondary cosmic-ray antiprotons is discussed. The flux expected on the basis of the usual picture of cosmic-ray propagation, including an energy-dependent confinement time, is calculated. It is also pointed out that kinematical features of the expected secondary-antiproton spectrum provide a possible way to discriminate between secondary antiprotons and a hypothetical primary $\overline{p}$ component in the cosmic radiation.