# Topology in QCD and the axion abundance

@article{Kitano2015TopologyIQ,
title={Topology in QCD and the axion abundance},
journal={Journal of High Energy Physics},
year={2015},
volume={2015},
pages={1-16}
}
• Published 1 June 2015
• Physics
• Journal of High Energy Physics
A bstractThe temperature dependence of the topological susceptibility in QCD, χt, essentially determines the abundance of the QCD axion in the Universe, and is commonly estimated, based on the instanton picture, to be a certain negative power of temperature. While lattice QCD should be able to check this behavior in principle, the temperature range where lattice QCD works is rather limited in practice, because the topological charge is apt to freezes at high temperatures. In this work, two…
Topology in full QCD at high temperature: a multicanonical approach
• Physics
Journal of High Energy Physics
• 2018
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Topological susceptibility at high temperature on the lattice
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• 2016
A bstractQCD topological susceptibility at high temperature, χt(T ), provides an important input for the estimate of the axion abundance in the present Universe. While the model independent
Axion phenomenology and θ-dependence from Nf = 2 + 1 lattice QCD
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Axions, Instantons, and the Lattice
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If the QCD axion is a significant component of dark matter, and if the universe was once hotter than a few hundred MeV, the axion relic abundance depends on the function $\chi(T)$, the
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We compute the effect of the chiral phase transition of Quantum Chromodynamics on the axion mass and self-coupling; the coupling of the axion to the quarks at finite temperature is described within

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