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DOE OSTI ยท 2575507

QCD axion: Some like it hot

Bianchini, Federico [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States); Stanford Univ., CA (United States). Kavli Institute for Particle Astrophysics & Cosmology] (ORCID:0000000348473483)ยทdi Cortona, Giovanni Grilli [National Inst. of Nuclear Physics (INFN), Rome (Italy)] (ORCID:0000000324086171)ยทValli, Mauro [National Inst. of Nuclear Physics (INFN), Rome (Italy)] (ORCID:0000000208993735)
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Abstract

We compare the quantum chromodynamics (QCD) axion phase-space distribution from unitarized next-to-leading order chiral perturbation theory with the one extracted from pion-scattering data. We derive a robust bound by confronting momentum-dependent Boltzmann equations against up-to-date observations of the cosmic microwave background, of the baryonic acoustic oscillations and of primordial abundances. These datasets imply ๐‘š ๐‘Ž โ‰ค 0.16 eV for the 95% credible interval, i.e., โˆผ 30% stronger bound than what previously found. We present forecasts using dedicated likelihoods for future cosmological surveys and the sphaleron rate from unquenched lattice QCD.

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79 ASTRONOMY AND ASTROPHYSICSBig bang nucleosynthesisCosmic microwave backgroundCosmological parametersLarge scale structure of the UniverseParticle dark matter

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BibTeXRIS

Bianchini, Federico [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States); Stanford Univ., CA (United States). Kavli Institute for Particle Astrophysics & Cosmology] (ORCID:0000000348473483), di Cortona, Giovanni Grilli [National Inst. of Nuclear Physics (INFN), Rome (Italy)] (ORCID:0000000324086171), Valli, Mauro [National Inst. of Nuclear Physics (INFN), Rome (Italy)] (ORCID:0000000208993735). 2024-12-17. QCD axion: Some like it hot. https://doi.org/10.1103/physrevd.110.123527

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