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arXiv · 1105.1773

Primordial non-Gaussianity from the 21 cm Power Spectrum during the Epoch of Reionization

Shahab Joudaki·Olivier Dore·Luis Ferramacho·Manoj Kaplinghat·Mario G. Santos
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Abstract

Primordial non-Gaussianity is a crucial test of inflationary cosmology. We consider the impact of non-Gaussianity on the ionization power spectrum from 21 cm emission during the epoch of reionization. We focus on the power spectrum on large scales at redshifts of 7 to 8 and explore the expected constraint on the local non-Gaussianity parameter f_NL for current and next-generation 21 cm experiments. We show that experiments such as SKA and MWA could measure f_NL values of order 10. This can be improved by an order of magnitude with a fast-Fourier transform telescope like Omniscope.

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Shahab Joudaki, Olivier Dore, Luis Ferramacho, Manoj Kaplinghat, Mario G. Santos. 2011-09-04. Primordial non-Gaussianity from the 21 cm Power Spectrum during the Epoch of Reionization. https://doi.org/10.1103/physrevlett.107.131304

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