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arXiv · 1910.09099

Log-dependent slope of scalar induced gravitational waves in the infrared regions

Chen Yuan·Zu-Cheng Chen·Qing-Guo Huang
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Abstract

We analytically calculate the scalar induced gravitational waves (SIGWs) and find a log-dependent slope of SIGW in the infrared regions $(f<f_c)$, namely $n_{\mathrm{GW}}(f)=3-2/\ln(f_c/f)$, and $n_{\mathrm{GW}}(f)=2-2/\ln(f_c/f)$ near the peak if the power spectrum of scalar curvature perturbation is quite narrow, where $f_c$ is roughly the frequency at the peak of SIGW. Such a log-dependent slope can be taken as a new template for distinguishing SIGW from other sources.

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Chen Yuan, Zu-Cheng Chen, Qing-Guo Huang. 2019-10-21. Log-dependent slope of scalar induced gravitational waves in the infrared regions. https://doi.org/10.1103/physrevd.101.043019

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