The soup that is not too hot

Abstract

The exploration of the QCD phase diagram is the goal of many experiments in the world. The low net baryon density region is relatively well studied, while the one corresponding to higher net densities still contains multiple unrevealed puzzles getting significant attention. In multiple experimental complexes such as STAR or HADES, the heavy ions collide at relatively lower energies than those obtained at LHC, creating "not the hottest soup" of nuclear matter. The examination of it provides unique insights into understanding the properties of matter production and its transitions. In this paper, several of the significant experimental discoveries are reviewed.