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arXiv · 1901.10152

Resonant multiple peaks in the induced gravitational waves

Rong-Gen Cai·Shi Pi·Shao-Jiang Wang·Xing-Yu Yang
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Abstract

We identify analytically a multiple-peak structure in the energy-density spectrum of induced gravitational waves (GWs) generated at second-order from a primordial scalar perturbations also with multiple($n$) peaks at small scales $k_{*i}$. The energy-density spectrum of induced GWs exhibits at most $C_{n+1}^2$ and at least $n$ peaks at wave-vectors $k_{ij}\equiv(k_{*i}+k_{*j})/\sqrt{3}$ due to resonant amplification, and, under the narrow-width approximation, it contains an universal factor that can be interpreted as a result of momentum conservation. We also extend these discussions to the case of non-Gaussian perturbations.

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Rong-Gen Cai, Shi Pi, Shao-Jiang Wang, Xing-Yu Yang. 2019-01-29. Resonant multiple peaks in the induced gravitational waves. https://doi.org/10.1088/1475-7516%2F2019%2F05%2F013

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