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

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.

7 pages, 5 figures, mnras accepted

References in corpus (11)

• Cosmology at Low Frequencies: The 21 cm Transition and the High-Redshift Universe
• UV Luminosity Functions at redshifts z~4 to z~10: 10000 Galaxies from HST Legacy Fields
• Observational constraints on Cosmic Reionization
• The evolution of the galaxy UV luminosity function at redshifts z ~ 8-15 from deep JWST and ground-based near-infrared imaging
• Improved upper limits on the 21-cm signal power spectrum of neutral hydrogen at $\mathbf{z}\approx 9.1$ from LOFAR
• Deep multi-redshift limits on Epoch of Reionisation 21cm Power Spectra from Four Seasons of Murchison Widefield Array Observations
• Constraining the intergalactic medium at $z\approx$ 9.1 using LOFAR Epoch of Reionization observations
• Constraining the state of the intergalactic medium during the Epoch of Reionization using MWA 21-cm signal observations
• Astrophysical Constraints from the SARAS3 non-detection of the Cosmic Dawn Sky-Averaged 21-cm Signal
• Sensitivity for 21cm Bispectrum from Epoch of Reionization
• Detection of Cosmic Structures using the Bispectrum Phase. II. First Results from Application to Cosmic Reionization Using the Hydrogen Epoch of Reionization Array