Thermal axion constraints in non-standard thermal histories

Daniel Grin; Tristan Smith; Marc Kamionkowski

doi:10.1063/1.3232168

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arXiv · 0812.4721

Thermal axion constraints in non-standard thermal histories

Daniel Grin·Tristan Smith·Marc Kamionkowski

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Abstract

There is no direct evidence for radiation domination prior to big-bang nucleosynthesis, and so it is useful to consider how constraints to thermally-produced axions change in non-standard thermal histories. In the low-temperature-reheating scenario, radiation domination begins at temperatures as low as 1 MeV, and is preceded by significant entropy generation. Axion abundances are then suppressed, and cosmological limits to axions are significantly loosened. In a kination scenario, a more modest change to axion constraints occurs. Future possible constraints to axions and low-temperature reheating are discussed.

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Daniel Grin, Tristan Smith, Marc Kamionkowski. 2009-11-10. Thermal axion constraints in non-standard thermal histories. https://doi.org/10.1063/1.3232168

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