Baryon stopping and strange baryon/antibaryon production at SPS energies
  The amount of proton stopping in central Pb+Pb collisions from 20-160 AGeV as well as hyperon and antihyperon rapidity distributions are calculated within the UrQMD model in comparison to experimental data at 40, 80 and 160 AGeV taken recently from the NA49 collaboration. Furthermore, the amount of baryon stopping at 160 AGeV for Pb+Pb collisions is studied as a function of centrality in comparison to the NA49 data. We find that the strange baryon yield is reasonably described for central collisions, however, the rapidity distributions are somewhat more narrow than the data. Moreover, the experimental antihyperon rapidity distributions at 40, 80 and 160 AGeV are underestimated by up to factors of 3 - depending on the annihilation cross section employed - which might be addressed to missing multi-meson fusion channels in the UrQMD model. 
H. Weber, E. L. Bratkovskaya and H. Stoecker (Univ. Frankfurt)