Abstract. A fundamental symmetry of nuclear and particle physics is isospin whose third component is the Gell-Mann/Nishijima expression I_Z=Q-(B+S)/2. The role of isospin symmetry in relativistic heavy-ion collisions is studied. An isospin I_Z, strangeness S correlation is shown to be a direct and simple measure of flavor correlations, vanishing in a Qg phase of uncorrelated flavors in both symmetric N=Z and asymmetric N≠Z systems. By contrast, in a hadron phase, a I_Z/S correlation exists as long as the electrostatic charge chemical potential μ_Q≠0 as in N≠Z asymmetric systems. A parallel is drawn with a Zeeman effect which breaks a spin degeneracy.

PACS numbers: 25.75.-q, 25.75.Gz, 25.75.Nq

Print publication: Issue 2 (October 2007)
Received 3 July 2007, accepted for publication 3 September 2007
Published 28 September 2007