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arXiv · 0904.3800

Axion isocurvature fluctuations with extremely blue spectrum

Shinta Kasuya·Masahiro Kawasaki
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Abstract

We construct an axion model for generating isocurvature fluctuations with blue spectrum, n_{iso}=2-4, which is suggested by recent analyses of admixture of adiabatic and isocurvature perturbations with independent spectral indices, n_{ad} \ne n_{iso}. The distinctive feature of the model is that the spectrum is blue at large scales while scale invariant at small scales. This is naturally realized by the dynamics of the Peccei-Quinn scalar field.

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Shinta Kasuya, Masahiro Kawasaki. 2009-08-05. Axion isocurvature fluctuations with extremely blue spectrum. https://doi.org/10.1103/physrevd.80.023516

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