Isospin and isospin/strangeness correlations in relativistic heavy-ion collisions

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 not equal Z systems. By contrast, in a hadron phase, a I-Z/ S correlation exists as long as the electrostatic charge chemical potential mu(Q) not equal 0 as in N not equal Z asymmetric systems. A parallel is drawn with a Zeeman effect which breaks a spin degeneracy. Copyright (C) EPLA, 2007.