Nuclear stopping power at ~15 GeV/nucleon.

Abstract

Fireball, firestreak, and hadronic string models are shown to overpredict recent central 15A GeV Si+Au E802 spectrometer data. Claims in the literature about full nuclear stopping in Si+Au reactions are therefore not supported by these data. In fact, fits to the spectrometer data indicate that up to half of the projectile nucleons may lose less than one unit of rapidity after traversing 5--10 fm of nuclear matter, implying an unexpected long stopping length of \ensuremath{\sim}20 fm. On the other hand, E810, E814, and preliminary E802 ${\mathit{dN}}_{\mathrm{ch}}$/d\ensuremath{\eta} data are more consistent with the expected degree of stopping.