Parton-Hadron-String Dynamics: an off-shell transport approach for relativistic energies

Understand

The dynamics of partons, hadrons and strings in relativistic nucleus-nucleus collisions is analyzed within the novel Parton-Hadron-String Dynamics (PHSD) transport approach, which is applied to Pb+Pb collisions from 20 to 160 A GeV in order to explore the space-time regions of 'partonic matter'.

• We find that even central collisions at the top-SPS energy of 158 A GeV show a large fraction of non-partonic, i.e.
• hadronic or string-like matter, which can be viewed as a hadronic corona.
• Furthermore, we observe that the partonic phase has a very low impact on rapidity distributions of hadrons but a sizeable influence on the transverse mass distribution of final kaons due to the repulsive partonic mean fields.