Lambda-nuclear interactions and hyperon puzzle in neutron stars

摘要: Brueckner theory is used to investigate the in-medium properties of a $\Lambda$ -hyperon in nuclear and neutron matter, based on hyperon-nucleon interactions derived within SU(3) chiral effective field (EFT). It shown that resulting $ \Lambda$ single-particle potential $U_{\Lambda}(p_{\Lambda} = 0,\rho)$ becomes strongly repulsive for densities $\rho$ two-to-three times normal matter. Adding density-dependent $\Lambda N$ -interaction constructed from NN$ three-body forces increases repulsion further. Consequences these findings stars are discussed. argued hyperon-nuclear with such as those deduced EFT potentials, onset hyperon formation core could be shifted much higher density which, turn, pave way resolving so-called puzzle.