Topology in QCD and the axion abundance

  title={Topology in QCD and the axion abundance},
  author={Ryuichiro Kitano and Norikazu Yamada},
  journal={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… 
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Instanton content of finite temperature QCD matter.
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