Strange baryons in a hot and dense medium within the Nambu-Jona-Lasinio model
Using an extended version of the Nambu-Jona-Lasinio model we build a simple description of the baryons as diquark-quark bound states. First, a description of the diquarks in a dense and hot medium is presented. Then, we introduce the formalism for the baryons based on the Faddeev equation associated with the so-called `` static approximation'' which finally gives a Bethe-Salpeter equation in the diquarks-quarks channel. By identifying the baryons with the bound states, we can obtain a description of their properties. In particular, we obtain the right mass spectrum for the proton, $\Lambda$, $\Xi$, and $\Sigma$ at T=0 and $\mu=0$. We extend the formalism to finite temperature and density to obtain a description of the mass change of these baryons in the medium.