We demonstrate that the observed cosmological excess of matter over anti-matter 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 ma between 1 MeV and 10 GeV and a decay constant fa< 105 GeV, which can be probed by accelerator-based direct axion searches and observations of the cosmic microwave background.
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- Axions and ALPs
- Baryo-and Leptogenesis
- Cosmology of Theories BSM
- Early Universe Particle Physics