부산대학교 도서관

Transverse hadron spectra from proton–proton, proton–nucleus and nucleus–nucleus collisions from 2 A GeV to 21.3 A TeV are investigated within two independent transport approaches (HSD and UrQMD). For central Au+Au (Pb+Pb) collisions at energies above E_lab ~ 5 A GeV, the measured K^± transverse mass spectra have a larger inverse slope parameter than expected from the default calculations. The additional pressure—as suggested by lattice QCD calculations at finite quark chemical potential μ_q and temperature T—might be generated by strong interactions in the early pre-hadronic/partonic phase of central Au+Au (Pb+Pb) collisions. This is supported by a non-monotonic energy dependence of v₂/〈p_T〉 in the present transport model.