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arXiv · 1510.07006

Cutoff in the Lyman-$\alpha$ forest power spectrum: warm IGM or warm dark matter?

Antonella Garzilli·Alexey Boyarsky·Oleg Ruchayskiy
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Abstract

We re-analyse high redshift and high resolution Lyman-$\alpha$ forest spectra considered in (Viel et al 2013), seeking to constrain the properties of warm dark matter particles. Compared to this previous work, we consider a wider range of thermal histories of the intergalactic medium. We find that both warm and cold dark matter models can explain the cut-off observed in the flux power spectra of high-resolution observations equally well. This implies, however, very different thermal histories and underlying re-ionisation models. We discuss how to remove this degeneracy.

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Antonella Garzilli, Alexey Boyarsky, Oleg Ruchayskiy. 2015-10-23. Cutoff in the Lyman-$\alpha$ forest power spectrum: warm IGM or warm dark matter?. https://doi.org/10.1016/j.physletb.2017.08.022

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