Inelasticity in p -nucleus collisions and its application to high energy cosmic-ray cascades

We employ a simple multiple scattering model to investigate the inclusive reaction p+A{r_arrow}p+X for projectile momenta in the 100{endash}200GeV/c range. We find that data are consistent with a class of interaction models in which the stopping power of nuclei is rather low. We discuss extrapolation to ultrahigh energy and the application to interpretation of cosmic-ray air showers at energies up to 10{sup 20}eV. {copyright} {ital 1997} {ital The American Physical Society}