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Can N-body systems generate periodic gravitational waves?

Takamasa Chiba·Tatsunori Imai·Hideki Asada
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Abstract

None of N-body gravitating systems have been considered to emit periodic gravitational waves because of their chaotic orbits when N=3 (or more). We employ a figure-eight orbit as a specific model for a 3-body system in order to illustrate that some of triple stars are capable of generating periodic waves. This illustration would imply that a certain class of N-body gravitating systems may be relevant to the gravitational waves generation. We show also that the total angular momentum of this 3-body system is not carried away by gravitational waves. A waveform generated by this system is volcano-shaped and thus different from that of a binary system. Finally, by evaluating the radiation reaction time scale, we give an order-of-magnitude estimate of merging event rates. The estimate suggests that figure-eight sources, which require carefully prepared initial states, may be too rare to detect.

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Takamasa Chiba, Tatsunori Imai, Hideki Asada. 2007-02-08. Can N-body systems generate periodic gravitational waves?. https://doi.org/10.1111/j.1365-2966.2007.11619.x

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