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

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 ${n}_{\mathrm{GW}}(f)=3\ensuremath{-}2/\mathrm{ln}({f}_{c}/f)$, and ${n}_{\mathrm{GW}}(f)=2\ensuremath{-}2/\mathrm{ln}({f}_{c}/f)$ near the peak if the power spectrum of scalar curvature perturbation is quite narrow, where ${f}_{c}$ is roughly the peak frequency. Such a log-dependent slope can be taken as a new template for distinguishing SIGW from other sources.

Topics & Concepts