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arXiv · 1904.02545

Fast-Rolling Relaxion

Masahiro Ibe·Yutaro Shoji·Motoo Suzuki
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Abstract

We discuss new mechanisms to stop the relaxion field during inflation. They can be realized in a generic model, including the original model but in a quite different parameter region. We consider a fast-rolling relaxion field, which can go over the bumps created by QCD-like dynamics. Then, in one of the mechanisms, we stop it with a parametric resonance of the Higgs field. The mechanisms are free from a super-Planckian field excursion or a gigantic number of e-folds of inflation. The relaxion has a mass around the weak scale and mixes with the Higgs boson, which enhances the testability of our mechanisms.

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Masahiro Ibe, Yutaro Shoji, Motoo Suzuki. 2019-11-27. Fast-Rolling Relaxion. https://doi.org/10.1007/jhep11(2019)140

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