The production of antiprotons due to collisions of primary cosmic rays with atmospheric nuclei is considered. On the basis of approximate experimental information on nuclear cross sections, an approximate value for the flux of antiprotons from this source is obtained. This flux is found to be about 5-50 times the flux of secondary antiprotons generated by cosmic-ray collisions with interstellar gas nuclei.

• Received 20 January 1967

DOI:https://doi.org/10.1103/PhysRev.160.1111