The momentum spectra of protons emitted from Be, C, Cu, and Pb nuclei bombarded by 1-, 2-, and 3-BeV protons from the Cosmotron have been measured at angles of 0°, 17°, and 32°. After correcting for scattering in the detectors, the spectra show reasonable agreement with Monte Carlo calculations of Bertini. However, the dependence on mass number $A$ requires a much larger value for the exponent of $A$ than is predicted by theory.

• Received 22 November 1968

DOI:https://doi.org/10.1103/PhysRev.183.849