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arXiv · 2004.02889

Fingerprint of Low-Scale Leptogenesis in the Primordial Gravitational-Wave Spectrum

Simone Blasi·Vedran Brdar·Kai Schmitz
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Abstract

The dynamical generation of right-handed-neutrino (RHN) masses in the early Universe naturally entails the formation of cosmic strings that give rise to an observable signal in gravitational waves (GWs). Here, we show that a characteristic break in the GW spectrum would provide evidence for a new stage in the cosmological expansion history and a suppression of the RHN mass scale compared to the scale of spontaneous symmetry breaking. The detection of such a spectral feature would thus represent a novel and unique possibility to probe the physics of RHN mass generation in regions of parameter space that allow for low-scale leptogenesis in accord with electroweak naturalness.

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Simone Blasi, Vedran Brdar, Kai Schmitz. 2020-04-06. Fingerprint of Low-Scale Leptogenesis in the Primordial Gravitational-Wave Spectrum. https://doi.org/10.1103/physrevresearch.2.043321

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