Can Decaying Particles Raise the Upperbound on the Peccei-Quinn Scale?
نویسندگان
چکیده
We have reexamine the effect of entropy production on the cosmic axion density and find that the Peccei-Quinn scale Fa larger than about 10 15 GeV is not allowed even if large entropy is produced by the decays of coherent oscillations or nonrelativistic massive particles. We stress that this result is independent of the details of models for the decaying particles.
منابع مشابه
Collapse of axionic domain wall and axion emission.
The axion [1{4] is the Nambu-Goldstone boson associated with the Peccei-Quinn symmetry breaking which was invented as the most natural solution to the strong CP problem [5] of QCD. The Peccei-Quinn symmetry breaking scale Fa is stringently constrained by the consideration of accelerator experiments, stellar cooling and cosmology. The allowed range of Fa=N ( axion window ) is between 10GeV and 1...
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