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Binary Neutron-Star Systems: From the Newtonian Regime to the Last Stable Orbit

P. Marronetti·G. J. Mathews·J. R. Wilson
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Abstract

We report on the first calculations of fully relativistic binary circular orbits to span a range of separation distances from the innermost stable circular orbit (ISCO), deeply inside the strong field regime, to a distance ($\sim$ 200 km) where the system is accurately described by Newtonian dynamics. We consider a binary system composed of two identical corotating neutron stars, with 1.43 $M_\odot$ gravitational mass each in isolation. Using a conformally flat spatial metric we find solutions to the initial value equations that correspond to semi-stable circular orbits. At large distance, our numerical results agree exceedingly well with the Newtonian limit. We also present a self consistent determination of the ISCO for different stellar masses.

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P. Marronetti, G. J. Mathews, J. R. Wilson. 1998-09-17. Binary Neutron-Star Systems: From the Newtonian Regime to the Last Stable Orbit. https://doi.org/10.1103/physrevd.58.107503

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