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arXiv · 1406.4332

Hyperon mixing and universal many-body repulsion in neutron stars

Y. Yamamoto·T. Furumoto·N. Yasutake·Th. A. Rijken
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Abstract

A multi-pomeron exchange potential (MPP) is proposed as a model for the universal many-body repulsion in baryonic systems on the basis of the Extended Soft Core (ESC) bryon-baryon interaction. The strength of MPP is determined by analyzing the nucleus-nucleus scattering with the G-matrix folding model. The interaction in $ΛN$ channels is shown to reproduce well the experimental $Λ$ binding energies. The equation of state (EoS) in neutron matter with hyperon mixing is obtained including the MPP contribution, and mass-radius relations of neutron stars are derived. It is shown that the maximum mass can be larger than the observed one $2M_{\odot}$ even in the case of including hyperon mixing on the basis of model-parameters determined by terrestrial experiments.

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Y. Yamamoto, T. Furumoto, N. Yasutake, Th. A. Rijken. 2014-06-17. Hyperon mixing and universal many-body repulsion in neutron stars. https://doi.org/10.1103/physrevc.90.045805

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