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arXiv · 1008.4528

Thermal axion production in the primordial quark-gluon plasma

Peter Graf·Frank Daniel Steffen
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Abstract

We calculate the rate for thermal production of axions via scattering of quarks and gluons in the primordial quark-gluon plasma. To obtain a finite result in a gauge-invariant way that is consistent to leading order in the strong gauge coupling, we use systematic field theoretical methods such as hard thermal loop resummation and the Braaten-Yuan prescription. The thermally produced yield, the decoupling temperature, and the density parameter are computed for axions with a mass below 10 meV. In this regime, with a Peccei-Quinn scale above 6x10^8 GeV, the associated axion population can still be relativistic today and can coexist with the axion cold dark matter condensate.

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Peter Graf, Frank Daniel Steffen. 2010-08-26. Thermal axion production in the primordial quark-gluon plasma. https://doi.org/10.1103/physrevd.83.075011

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