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A practical formula for the radiated angular momentum

Carlos O. Lousto·Yosef Zlochower
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Abstract

We present a simple formula for the radiated angular momentum based on a spin-weighted spherical harmonic decomposition of the Weyl scalar psi_4 representing outgoing radiation in the Kinnersley tetrad. We test our formula by measuring the radiated angular momentum from three simulations of non-spinning equal-mass black-hole binary with orbital angular momentum aligned along the x, y, and z axes respectively. We find that the radiated angular momentum agrees with the differences in the remnant horizon spins and the initial angular momentum for each system.

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Carlos O. Lousto, Yosef Zlochower. 2007-06-10. A practical formula for the radiated angular momentum. https://doi.org/10.1103/physrevd.76.041502

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