Impacts and Statistical Mitigation of Missing Data on the 21cm Power Spectrum: A Case Study with the Hydrogen Epoch of Reionization Array
Abstract
The precise characterization and mitigation of systematic effects is one of the biggest roadblocks impeding the detection of the fluctuations of cosmological 21cm signals. Missing data in radio cosmological experiments, often due to radio frequency interference (RFI), poses a particular challenge to power spectrum analysis as it could lead to the ringing of bright foreground modes in Fourier space, heavily contaminating the cosmological signals. Here we show that the problem of missing data becomes even more arduous in the presence of systematic effects. Using a realistic numerical simulation, we demonstrate that partially flagged data combined with systematic effects can introduce significant foreground ringing. We show that such an effect can be mitigated through inpainting the missing data. We present a rigorous statistical framework that incorporates the process of inpainting missing data into a quadratic estimator of the 21cm power spectrum. Under this framework, the uncertainties associated with our inpainting method and its impact on power spectrum statistics can be understood. These results are applied to the latest Phase II observations taken by the Hydrogen Epoch of Reionization Array, forming a crucial component in power spectrum analyses as we move toward detecting 21cm signals in the ever more noisy RFI environment.
Keywords
Cite
@article{arxiv.2411.10529,
title = {Impacts and Statistical Mitigation of Missing Data on the 21cm Power Spectrum: A Case Study with the Hydrogen Epoch of Reionization Array},
author = {Kai-Feng Chen and Michael J. Wilensky and Adrian Liu and Joshua S. Dillon and Jacqueline N. Hewitt and Tyrone Adams and James E. Aguirre and Rushelle Baartman and Adam P. Beardsley and Lindsay M. Berkhout and Gianni Bernardi and Tashalee S. Billings and Judd D. Bowman and Philip Bull and Jacob Burba and Ruby Byrne and Steven Carey and Samir Choudhuri and Tyler Cox and David R. DeBoer and Matt Dexter and Nico Eksteen and John Ely and Aaron Ewall-Wice and Steven R. Furlanetto and Kingsley Gale-Sides and Hugh Garsden and Bharat Kumar Gehlot and Adélie Gorce and Deepthi Gorthi and Ziyaad Halday and Bryna J. Hazelton and Jack Hickish and Daniel C. Jacobs and Alec Josaitis and Nicholas S. Kern and Joshua Kerrigan and Piyanat Kittiwisit and Matthew Kolopanis and Paul La Plante and Adam Lanman and Yin-Zhe Ma and David H. E. MacMahon and Lourence Malan and Cresshim Malgas and Keith Malgas and Bradley Marero and Zachary E. Martinot and Lisa McBride and Andrei Mesinger and Nicel Mohamed-Hinds and Mathakane Molewa and Miguel F. Morales and Steven G. Murray and Hans Nuwegeld and Aaron R. Parsons and Robert Pascua and Yuxiang Qin and Eleanor Rath and Nima Razavi-Ghods and James Robnett and Mario G. Santos and Peter Sims and Saurabh Singh and Dara Storer and Hilton Swarts and Jianrong Tan and Pieter van Wyngaarden and Haoxuan Zheng},
journal= {arXiv preprint arXiv:2411.10529},
year = {2024}
}
Comments
25 pages, 11 figures; Replaced to match accepted ApJ version. New version contains small editorial changes throughout in response to referee comments, no changes to results