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

TL;DR

This paper examines baryon stopping and transport in central heavy-ion collisions at SPS and RHIC energies, finding a linear increase in fragmentation-peak positions with beam rapidity consistent with QCD saturation models, with no abrupt changes at transition energies.

Contribution

It provides experimental data on baryon stopping across a range of energies and confirms the linear growth of fragmentation peaks predicted by a QCD-based saturation model.

Findings

Fragmentation-peak positions grow linearly with beam rapidity.

No discontinuities observed in the transition region from partons to hadrons.

Results support gluon saturation models in high-energy collisions.

Abstract

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.