No 1 THE T – μ PHASE DIAGRAM OF THE NAMBU – JONA-LASINIO MODEL IN THE PRESENCE OF EXPLICIT SYMMETRY-BREAKING INTERACTIONS ∗

It is shown that the strange-quark mass undergoes a first-order transition in a generalized 3 flavor Nambu–Jona-Lasinio (NJL) Lagrangian which includes a complete set of explicit chiral symmetry breaking interactions. This transition occurs in a moderate chemical potential region μ ∼ 400 MeV, in addition to the usual chiral transition associated with the light-quark sector. This favors the formation of stable strange-quark matter at chemical potentials which are considerably lower than the ones discussed in the literature. The reason for this behavior is discussed.