The $T-\mu$ phase diagram of the NJL 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 $\mu \sim 400$ 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.