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arXiv · 2308.13134

Enhancement of gravitational waves at Q-ball decay including non-linear density perturbations

Masahiro Kawasaki·Kai Murai
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Abstract

The existence of a stochastic gravitational wave background is indicated by the recent pulsar timing array (PTA) experiments. We study the enhanced production of second-order gravitational waves from the scalar perturbations when the universe experiences a transition from the early matter-dominated era to the radiation-dominated era due to Q-ball decay. We extend the analysis in previous work by including the frequency range where density perturbations go non-linear and find that the resultant gravitational wave spectrum can be consistent with that favored by the recent PTA experiment results.

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Masahiro Kawasaki, Kai Murai. 2023-08-25. Enhancement of gravitational waves at Q-ball decay including non-linear density perturbations. https://doi.org/10.1088/1475-7516%2F2024%2F01%2F050

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