Thermal hadron production in relativistic nuclear collisions

TL;DR

This paper improves the statistical model of hadron production in nuclear collisions by including high-mass resonances and the scalar sigma meson, successfully explaining the energy dependence of particle ratios.

Contribution

It introduces the inclusion of high-mass resonances and the scalar sigma meson into the statistical model, enhancing the description of experimental data in nuclear collisions.

Findings

Better reproduction of the K+/pi+ ratio energy dependence

Connection to Hagedorn's limiting temperature established

Enhanced agreement with experimental hadron production data

Abstract

We present the status of the description of hadron production in central nucleus-nucleus collisions within the statistical model . Extending previous studies by inclusion of very high-mass resonances (m>2 GeV), and the up-to-now neglected scalar $\sigma$ meson leads to an improved description of the data. In particular, the hitherto poorly reproduced energy dependence of the K+/pi+ ratio at SPS energies ("the horn") is now well described through the connection to the hadronic mass spectrum and, implicitly, Hagedorn's limiting temperature.