A relativistic formalism for computation of irrotational binary stars in quasi equilibrium states

TL;DR

This paper introduces a new, simplified relativistic formalism for calculating irrotational binary neutron stars in quasi-equilibrium states, applicable in numerical relativity and post-Newtonian approximations.

Contribution

It provides a novel set of relativistic hydrostatic equations that are simpler and more computationally tractable than previous formulations for binary neutron star systems.

Findings

New relativistic hydrostatic equations for binary stars

Equations applicable in 3+1 formalism and post-Newtonian order

Enhanced computational efficiency for numerical relativity simulations

Abstract

We present relativistic hydrostatic equations for obtaining irrotational binary neutron stars in quasi equilibrium states in 3+1 formalism. Equations derived here are different from those previously given by Bonazzola, Gourgoulhon, and Marck, and have a simpler and more tractable form for computation in numerical relativity. We also present hydrostatic equations for computation of equilibrium irrotational binary stars in first post-Newtonian order.