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arXiv · 0708.2720

Simulating binary neutron stars: dynamics and gravitational waves

Matthew Anderson·Eric W. Hirschmann·Luis Lehner·Steven L. Liebling·Patrick M. Motl·David Neilsen·Carlos Palenzuela·Joel E. Tohline
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Abstract

We model two mergers of orbiting binary neutron stars, the first forming a black hole and the second a differentially rotating neutron star. We extract gravitational waveforms in the wave zone. Comparisons to a post-Newtonian analysis allow us to compute the orbital kinematics, including trajectories and orbital eccentricities. We verify our code by evolving single stars and extracting radial perturbative modes, which compare very well to results from perturbation theory. The Einstein equations are solved in a first order reduction of the generalized harmonic formulation, and the fluid equations are solved using a modified convex essentially non-oscillatory method. All calculations are done in three spatial dimensions without symmetry assumptions. We use the \had computational infrastructure for distributed adaptive mesh refinement.

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Matthew Anderson, Eric W. Hirschmann, Luis Lehner, Steven L. Liebling, Patrick M. Motl, David Neilsen, Carlos Palenzuela, Joel E. Tohline. 2008-01-04. Simulating binary neutron stars: dynamics and gravitational waves. https://doi.org/10.1103/physrevd.77.024006

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