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arXiv · 2203.15599

Signature of primordial non-Gaussianity on 21-cm power spectrum from dark ages

Daisuke Yamauchi
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Abstract

We study the signature of primordial non-Gaussianity imprinted on the power spectrum of the 21-cm line differential brightness temperature during dark ages. Employing the perturbative treatment of gravitational clustering, we quantitatively estimate the effects of the non-Gaussian and one-loop corrections on the 21-cm power spectrum. The potential impact of the use of the 21-cm power spectrum for the constraint on local-type primordial non-Gaussianity is investigated based on the Fisher matrix analysis. Our results show that the 21-cm power spectrum for an array with a baseline of several tens of kilometers can constrain the primordial non-Gaussianity to a level severer than that from cosmic microwave background measurements and its constraining power is stronger than that of the 21-cm bispectrum, while in the ultimate situation the 21-cm bispectrum eventually becomes more powerful.

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Daisuke Yamauchi. 2022-03-29. Signature of primordial non-Gaussianity on 21-cm power spectrum from dark ages. https://arxiv.org/abs/2203.15599

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