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arXiv · hep-ph/9510461

Can Decaying Particles Raise the Upperbound on the Peccei-Quinn Scale?

M. Kawasaki·T. Moroi·T. Yanagida
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Abstract

We have reexamine the effect of entropy production on the cosmic axion density and find that the Peccei-Quinn scale $F_a$ larger than about $10^{15}$~GeV is not allowed even if large entropy is produced by the decays of coherent oscillations or non-relativistic massive particles. We stress that this result is independent of the details of models for the decaying particles.

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M. Kawasaki, T. Moroi, T. Yanagida. 1995-11-01. Can Decaying Particles Raise the Upperbound on the Peccei-Quinn Scale?. https://doi.org/10.1016/0370-2693(96)00743-5

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