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arXiv · 0809.0002

Evolving black hole-neutron star binaries in general relativity using pseudospectral and finite difference methods

Matthew D. Duez·Francois Foucart·Lawrence E. Kidder·Harald P. Pfeiffer·Mark A. Scheel·Saul A. Teukolsky
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Abstract

We present a code for solving the coupled Einstein-hydrodynamics equations to evolve relativistic, self-gravitating fluids. The Einstein field equations are solved in generalized harmonic coordinates on one grid using pseudospectral methods, while the fluids are evolved on another grid using shock-capturing finite difference or finite volume techniques. We show that the code accurately evolves equilibrium stars and accretion flows. Then we simulate an equal-mass nonspinning black hole-neutron star binary, evolving through the final four orbits of inspiral, through the merger, to the final stationary black hole. The gravitational waveform can be reliably extracted from the simulation.

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Matthew D. Duez, Francois Foucart, Lawrence E. Kidder, Harald P. Pfeiffer, Mark A. Scheel, Saul A. Teukolsky. 2008-09-05. Evolving black hole-neutron star binaries in general relativity using pseudospectral and finite difference methods. https://doi.org/10.1103/physrevd.78.104015

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