Fast-Rolling Relaxion

Understand

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.