https://doi.org/10.1140/epja/i2017-12316-4
Regular Article - Theoretical Physics
Lambda-nuclear interactions and hyperon puzzle in neutron stars
1
Institute for Advanced Simulation, Institut für Kernphysik and Jülich Center for Hadron Physics, Forschungszentrum Jülich, D-52425, Jülich, Germany
2
Helmholtz Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universität Bonn, D-53115, Bonn, Germany
3
Physik Department, Technische Universität München, D-85747, Garching, Germany
* e-mail: j.haidenbauer@fz-juelich.de
Received:
30
January
2017
Accepted:
13
May
2017
Published online:
14
June
2017
Brueckner theory is used to investigate the in-medium properties of a -hyperon in nuclear and neutron matter, based on hyperon-nucleon interactions derived within SU(3) chiral effective field theory (EFT). It is shown that the resulting
single-particle potential
becomes strongly repulsive for densities
of two-to-three times that of normal nuclear matter. Adding a density-dependent effective
-interaction constructed from chiral
three-body forces increases the repulsion further. Consequences of these findings for neutron stars are discussed. It is argued that for hyperon-nuclear interactions with properties such as those deduced from the SU(3) EFT potentials, the onset for hyperon formation in the core of neutron stars could be shifted to much higher density which, in turn, could pave the way for resolving the so-called hyperon puzzle.
© SIF, Springer-Verlag GmbH Germany, 2017