Axiogenesis with a Heavy QCD Axion

Abstract

We demonstrate that the observed cosmological excess of matter over antimatter may originate from a heavy QCD axion that solves the strong CP problem but has a mass much larger than that given by the Standard Model QCD strong dynamics. We investigate a rotation of the heavy QCD axion in field space, which is transferred into a baryon asymmetry through weak and strong sphaleron processes. This provides a strong cosmological motivation for heavy QCD axions, which are of high experimental interest. The viable parameter space has an axion mass $m_a$ between 1~MeV and 10 GeV and a decay constant $f_a<10^5$ GeV, which can be probed by accelerator-based direct axion searches and observations of the cosmic microwave background.

37 pages, 6 figures

References in corpus (8)

• The Sphaleron Rate in the Minimal Standard Model
• Revised constraints and Belle II sensitivity for visible and invisible axion-like particles
• Anomalous solutions to the strong CP problem
• Dynamics of oscillating scalar field in thermal environment
• Moduli decay in the hot early Universe
• On bulk viscosity and moduli decay
• Enhanced EDMs from Small Instantons
• Charge transfer between rotating complex scalar fields

Cited by in corpus (1)

• First Constraints on Heavy QCD Axions with a Liquid Argon Time Projection Chamber using the ArgoNeuT Experiment