Pion and kaon production in central Pb+Pb collisions at 20A and 30A GeV: Evidence for the onset of deconfinement

TL;DR

This paper presents evidence for the onset of deconfinement in central Pb+Pb collisions, showing a rapid change in pion and kaon production around 30A GeV, supporting the transition to deconfined matter.

Contribution

It provides experimental data indicating the energy threshold for deconfinement at SPS energies, highlighting a significant change in particle production patterns.

Findings

Rapid change in pion and kaon yields around 30A GeV

Evidence supporting the onset of deconfinement at SPS energies

Altered transverse mass spectra shape near 30A GeV

Abstract

Results on charged pion and kaon production in central Pb+Pb collisions at 20A and 30A GeV are presented and compared to data at lower and higher energies. A rapid change of the energy dependence is observed around 30A GeV for the yields of pions and kaons as well as for the shape of the transverse mass spectra. The change is compatible with the prediction that the threshold for production of a state of deconfined matter at the early stage of the collisions is located at low SPS energies.