Stopping in central Pb + Pb collisions at SPS energies and beyond

Understand

We investigate stopping and baryon transport in central relativistic Pb + Pb and Au + Au collisions.

• At energies reached at the CERN Super Proton Synchrotron [sqrt(s_NN) = 6.3-17.3 GeV] and at RHIC (62.4 GeV), we determine the fragmentation-peak positions from the data.
• The resulting linear growth of the peak positions with beam rapidity is in agreement with our results from a QCD-based approach that accounts for gluon saturation.
• No discontinuities in the net-proton fragmentation peak positions occur in the expected transition region from partons to hadrons at 6-10 GeV.