An experimental measurement of the coexistence curve and critical temperature, density and pressure of bulk nuclear matter

TL;DR

This paper measures the critical parameters of bulk nuclear matter, such as temperature, density, and pressure, using experimental data from multiple nuclear reactions analyzed with a modified Fisher's droplet model.

Contribution

It provides the first experimental determination of the nuclear matter critical point parameters using diverse reaction data and a tailored theoretical model.

Findings

Critical temperature: 17.9+-0.4 MeV

Critical density: 0.06+-0.01 nucleons/fm^3

Critical pressure: 0.31+-0.07 MeV/fm^3

Abstract

Infinite, neutron-proton symmetric, neutral nuclear matter has a critical temperature of 17.9+-0.4 MeV, a critical density of 0.06+-0.01 nucleons per cubic fermi and a critical pressure of 0.31+-0.07 MeV per cubic fermi. These values have been obtained from our analysis of data from six different reactions studied in three different experiments: two "compound nuclear" reactions: 58Ni+12C-->70Se and 64Ni+12C-->76Se (both performed at the LBNL 88" Cyclotron) and four "multifragmentation" reactions: 1 GeV/c pi+197Au (performed by the ISiS collaboration), 1 AGeV 197Au+C, 1 AGeV 139La+12C and 1 AGeV 84Kr+12C (all performed by the EOS collaboration). The charge yields of all reactions as a function of excitation energy were fit with a version of Fisher's droplet model modified to account for the dual components of the fluid (i.e. protons and neutrons), Coulomb effects, finite size effects and angular momentum arising from the nuclear collisions.