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arXiv · 2206.00678

Axiogenesis with a Heavy QCD Axion

Raymond T. Co·Tony Gherghetta·Keisuke Harigaya
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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.

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Raymond T. Co, Tony Gherghetta, Keisuke Harigaya. 2022-06-01. Axiogenesis with a Heavy QCD Axion. https://doi.org/10.1007/jhep10(2022)121

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