%0 Generic %1 mondal2021epoch %A Mondal, Rajesh %A Mellema, Garrelt %A Shaw, Abinash Kumar %A Kamran, Mohd %A Majumdar, Suman %D 2021 %K library %T The Epoch of Reionization 21-cm Bispectrum -- I: The impact of light-cone effects and detectability %U http://arxiv.org/abs/2107.02668 %X We study the spherically averaged bispectrum of the 21-cm signal from the Epoch of Reionization (EoR). This metric provides a quantitative measurement of the level of non-Gaussianity of the signal which is expected to be high. We focus on the impact of the light-cone effect on the bispectrum and its detectability with the future SKA-Low telescope. Our investigation is based on semi-numerical light-cone simulation and an ensemble of 50 independent realisations of the 21-cm signal to estimate the cosmic variance errors. We calculate the bispectrum with a new, optimised direct estimation method, DviSukta which calculates the bispectrum for all possible unique triangles. We find that the light-cone effect becomes important on scales $k_1 łesssim 0.1\,Mpc^-1$ where for most triangle shapes the cosmic variance errors dominate. Only for the squeezed limit triangles, the impact of the light-cone effect exceeds the cosmic variance. Combining the effects of system noise and cosmic variance we find that $3\sigma$ detection of the bispectrum is possible for all unique triangle shapes around a scale of $k_1 0.2\,\rm Mpc^-1$, and cosmic variance errors dominate above and noise errors below this length scale. Only the squeezed limit triangles are able to achieve a more than $5\sigma$ significance over a wide range of scales, $k_1 łesssim 0.8\,Mpc^-1$. Our results suggest that among all the possible triangle combinations for the bispectrum, the squeezed limit one will be the most measurable and hence useful.

@misc{mondal2021epoch, abstract = {We study the spherically averaged bispectrum of the 21-cm signal from the Epoch of Reionization (EoR). This metric provides a quantitative measurement of the level of non-Gaussianity of the signal which is expected to be high. We focus on the impact of the light-cone effect on the bispectrum and its detectability with the future SKA-Low telescope. Our investigation is based on semi-numerical light-cone simulation and an ensemble of 50 independent realisations of the 21-cm signal to estimate the cosmic variance errors. We calculate the bispectrum with a new, optimised direct estimation method, DviSukta which calculates the bispectrum for all possible unique triangles. We find that the light-cone effect becomes important on scales $k_1 \lesssim 0.1\,{\rm Mpc}^{-1}$ where for most triangle shapes the cosmic variance errors dominate. Only for the squeezed limit triangles, the impact of the light-cone effect exceeds the cosmic variance. Combining the effects of system noise and cosmic variance we find that $\sim 3\sigma$ detection of the bispectrum is possible for all unique triangle shapes around a scale of $k_1 \sim 0.2\,{\rm Mpc}^{-1}$, and cosmic variance errors dominate above and noise errors below this length scale. Only the squeezed limit triangles are able to achieve a more than $5\sigma$ significance over a wide range of scales, $k_1 \lesssim 0.8\,{\rm Mpc}^{-1}$. Our results suggest that among all the possible triangle combinations for the bispectrum, the squeezed limit one will be the most measurable and hence useful.}, added-at = {2021-07-07T07:35:56.000+0200}, author = {Mondal, Rajesh and Mellema, Garrelt and Shaw, Abinash Kumar and Kamran, Mohd and Majumdar, Suman}, biburl = {https://www.bibsonomy.org/bibtex/27db32c536993d16baa073abe02870f4a/gpkulkarni}, description = {The Epoch of Reionization 21-cm Bispectrum -- I: The impact of light-cone effects and detectability}, interhash = {3b6883fbfe29161649d05ea91f086db0}, intrahash = {7db32c536993d16baa073abe02870f4a}, keywords = {library}, note = {cite arxiv:2107.02668Comment: 12 pages, 13 figures, comments are welcome}, timestamp = {2021-07-07T07:35:56.000+0200}, title = {The Epoch of Reionization 21-cm Bispectrum -- I: The impact of light-cone effects and detectability}, url = {http://arxiv.org/abs/2107.02668}, year = 2021 }