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arXiv · 2209.07693

Gravitational waves from primordial scalar and tensor perturbations

Zhe Chang·Xukun Zhang·Jing-Zhi Zhou
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Abstract

We investigate the second order gravitational waves induced by the primordial scalar and tensor perturbations during radiation-dominated era. The explicit expressions of the power spectra of the second order GWs are presented. We calculate the energy density spectra of the second order GWs for a monochromatic primordial power spectra. For large $k$ $\left( k>k_* \right)$, the effects of the primordial tensor perturbation with tensor-to-scalar ratio $r=A_{h}/A_{\zeta}=0.2$ lead to an around $50\% $ increase of the signal-to-noise ratio (SNR) for LISA observations.

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Zhe Chang, Xukun Zhang, Jing-Zhi Zhou. 2022-09-16. Gravitational waves from primordial scalar and tensor perturbations. https://doi.org/10.1103/physrevd.107.063510

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