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arXiv · 2407.10908

Angular Momentum Flux in Scalar-Tensor Theories up to 1.5 post-Newtonian Order

Tamanna Jain·Piero Rettegno
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Abstract

We compute the angular momentum flux from a non-circular nonspinning binary system of compact objects in massless scalar-tensor theories up to one and a half post-Newtonian (1.5PN) order using multipole moments. The angular momentum flux in scalar-tensor theories involves both a tensorial and a scalar contribution which can be further decomposed as instantaneous, tail and non-linear memory effects up to 1.5PN order. We compute the explicit expressions of tail effects using the Fourier decomposition of tensorial and scalar multipole moments, and non-linear memory effects using the Newtonian order quasi-Keplerian representation of elliptic orbits in scalar-tensor theories. This work is important to construct the radiation-reaction force and hence the waveform templates for eccentric binaries in scalar-tensor theories of gravity.

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Tamanna Jain, Piero Rettegno. 2024-07-15. Angular Momentum Flux in Scalar-Tensor Theories up to 1.5 post-Newtonian Order. https://arxiv.org/abs/2407.10908

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