EXOTIC MATTER CORES. “In case of low mass compact stars too, the core matter density is much larger than the normal matter. Due to extreme density, nuclear matter may consist not only of nucleons and leptons but also several exotic components in their different forms and phases such as Bose–Einstein condensates of strange mesons, hyperons, and baryon resonances, as well as strange quark matter.”
https://www.sciencedirect.com/science/article/pii/S221268642030039X