Baryon recoil and the fragmentation regions in ultra-relativistic nuclear collisions

The purpose of this paper is to reinvestigate the description of the fragmentation regions of ultrarelativistic nuclear collisions. Also, the authors update the estimates of energy density reached by incorporating recent nuclear stopping power results. They find that most of the discrepancy between kinetic and hydrodynamic estimates resulted from the lack of exact baryon conservation in the hydrodynamic formulation. They formulate a new hydrodynamic model preserving the continuity equation in a way that nevertheless allows them to incorporate large baryon recoil observed empirically. This model leads to significantly higher energy densities than even the earliest estimates suggested. Therefore, the prospects for studying high baryon density plasmas look better than ever