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arXiv · 1806.09832

Effects of Chiral Effective Field Theory Equation of State on Binary Neutron Star Mergers

Abstract

We present fully general relativistic simulations of binary neutron star mergers, employing a new zero- temperature chiral effective field theory equation of state, the BL EOS. We offer a comparison with respect to the older GM3 EOS, which is based on standard relativistic mean field theory, and separately determine the impact of the mass. We provide a detailed analysis of the dynamics, with focus on the post-merger phase. For all models, we extract the gravitational wave strain and the post-merger frequency spectrum. Further, we determine the amount, velocity, and polar distribution of ejected matter, and provide estimates for the resulting kilonova signals. We also study the evolution of the disk while it is interacting with the hypermassive remnant, and dis- cuss the merits of different disk mass definitions applicable before collapse, with regard to the mass remaining after BH formation. Finally, we investigate the radial mass distribution and rotation profile of the remnants, which validate previous results and also corroborate a recently proposed stability criterion.

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Andrea Endrizzi, Domenico Logoteta, Bruno Giacomazzo, Ignazio Bombaci, Wolfgang Kastaun, Riccardo Ciolfi. 2018-09-05. Effects of Chiral Effective Field Theory Equation of State on Binary Neutron Star Mergers. https://doi.org/10.1103/physrevd.98.043015

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