Mass dependence of the proton inclusive cross section for high energy nucleus-nucleus collisions

We show that while the mass number dependences of the proton inclusive cross section measured in collisions of near-equal mass nuclei at 800 MeV/nucleon can, over a wide range of energies, be reproduced reasonably well by simplified multiple scattering models based on independent nucleon nucleon collisions, definite discrepancies show up at very high transverse momentum. Possible reasons for these deviations are discussed