Axiogenesis and Ultralight Dark Matter

We proposed a mechanism called axiogenesis to explain the observed baryon asymmetry from the rotation of the QCD axion field and the Standard Model sphaleron processes. In the concrete model we explored, rich phenomenology arises due to the connection with a small decay constant, TeV-scale particles, and axion dark matter. In regard to ultralight dark matter, we propose new non-thermal production mechanisms for QCD axions and dark photons. via parametric resonance and tachyonic instability, respectively. These ideas expand the parameter space to the regions of interest for the extensive experimental searches. Other potential signatures include dark matter ultracompact minihalos, warm dark matter, and gravitational waves.

Host: Xue Wei