Nuclear stopping power

The recent data on p + A → p + X at 100 GeV have generated a great deal of interest in nuclear stopping power. The first analysis of that data indicated that a high energy proton can lose over 90% of its initial energy when penetrating the diameter of a heavy nucleus. This is a surprise in light of a decade of previous data indicating that nuclei are rather transparent at high energies. In terms of rapidity shift it appeared that up to 2.5 units of rapidity loss is possible. If the data, and interpretations are correct, then they have profound consequences for the energy density that could be generated in nuclear collisions between 10 and 100 GeV/nucleon. Because of the importance of this conclusion the authors reanalyzed the data using the multichain model which allows (1) treatment of diffuse nuclear geometry, (2) differential energy loss, and (3) secondary (π, K, ...) production