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arXiv · 0912.3125

Toward a dynamical shift condition for unequal mass black hole binary simulations

Doreen Mueller·Bernd Bruegmann
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Abstract

Moving puncture simulations of black hole binaries rely on a specific gauge choice that leads to approximately stationary coordinates near each black hole. Part of the shift condition is a damping parameter, which has to be properly chosen for stable evolutions. However, a constant damping parameter does not account for the difference in mass in unequal mass binaries. We introduce a position dependent shift damping that addresses this problem. Although the coordinates change, the changes in the extracted gravitational waves are small.

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Doreen Mueller, Bernd Bruegmann. 2009-12-16. Toward a dynamical shift condition for unequal mass black hole binary simulations. https://doi.org/10.1088/0264-9381%2F27%2F11%2F114008

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