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arXiv · 2305.06514

Skew spectrum and smoothed skewness of 21-cm signals from epoch of reionization

Qing-Bo Ma·Ling Peng
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Abstract

Due to the non-linear ionizing and heating processes, the 21-cm signals from epoch of reionization (EoR) are expected to have strong non-Gaussian fluctuations. In this paper, we use the semi-numerical simulations to study the non-Gaussian statistics i.e. skew spectrum and smoothed skewness of the 21-cm signals from EoR. We find the 21-cm skew spectrum and smoothed skewness have similar evolution features with the 21-cm bispectrum. All of them are sensitive to the EoR models, while not too much to the cosmic volume applied. With the SKA1-low telescope as reference, we find both the skew spectrum and smoothed skewness have much higher S/N ratios than the 21-cm bispectrum.

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Qing-Bo Ma, Ling Peng. 2023-05-11. Skew spectrum and smoothed skewness of 21-cm signals from epoch of reionization. https://doi.org/10.1093/mnras%2Fstad1447

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