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arXiv · 2204.06021

Direct Optimal Mapping for 21cm Cosmology: A Demonstration with the Hydrogen Epoch of Reionization Array

Zhilei Xu·Jacqueline N. Hewitt·Kai-Feng Chen·Honggeun Kim·Joshua S. Dillon·Nicholas S. Kern·Miguel F. Morales·Bryna J. Hazelton·Ruby Byrne·Nicolas Fagnoni·Eloy de Lera Acedo·Zara Abdurashidova·Tyrone Adams·James E. Aguirre·Paul Alexander·Zaki S. Ali·Rushelle Baartman·Yanga Balfour·Adam P. Beardsley·Gianni Bernardi·Tashalee S. Billings·Judd D. Bowman·Richard F. Bradley·Philip Bull·Jacob Burba·Steven Carey·Chris L. Carilli·Carina Cheng·David R. DeBoer·Matt Dexter·Nico Eksteen·John Ely·Aaron Ewall-Wice·Randall Fritz·Steven R. Furlanetto·Kingsley Gale-Sides·Brian Glendenning·Deepthi Gorthi·Bradley Greig·Jasper Grobbelaar·Ziyaad Halday·Jack Hickish·Daniel C. Jacobs·Austin Julius·MacCalvin Kariseb·Joshua Kerrigan·Piyanat Kittiwisit·Saul A. Kohn·Matthew Kolopanis·Adam Lanman·Paul La Plante·Adrian Liu·Anita Loots·Yin-zhe Ma·David Harold Edward MacMahon·Lourence Malan·Cresshim Malgas·Keith Malgas·Bradley Marero·Zachary E. Martinot·Andrei Mesinger·Mathakane Molewa·Tshegofalang Mosiane·Steven G. Murray·Abraham R. Neben·Bojan Nikolic·Hans Nuwegeld·Aaron R. Parsons·Nipanjana Patra·Samantha Pieterse·Jonathan C. Pober·Nima Razavi-Ghods·James Robnett·Kathryn Rosie·Peter Sims·Craig Smith·Hilton Swarts·Nithyanandan Thyagarajan·Pieter Van Van Wyngaarden·Peter K. G. Williams·Haoxuan Zheng
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Abstract

Motivated by the desire for wide-field images with well-defined statistical properties for 21cm cosmology, we implement an optimal mapping pipeline that computes a maximum likelihood estimator for the sky using the interferometric measurement equation. We demonstrate this direct optimal mapping with data from the Hydrogen Epoch of Reionization (HERA) Phase I observations. After validating the pipeline with simulated data, we develop a maximum likelihood figure-of-merit for comparing four sky models at 166MHz with a bandwidth of 100kHz. The HERA data agree with the GLEAM catalogs to <10%. After subtracting the GLEAM point sources, the HERA data discriminate between the different continuum sky models, providing most support for the model of Byrne et al. 2021. We report the computation cost for mapping the HERA Phase I data and project the computation for the HERA 320-antenna data; both are feasible with a modern server. The algorithm is broadly applicable to other interferometers and is valid for wide-field and non-coplanar arrays.

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Zhilei Xu, Jacqueline N. Hewitt, Kai-Feng Chen, Honggeun Kim, Joshua S. Dillon, Nicholas S. Kern, Miguel F. Morales, Bryna J. Hazelton, Ruby Byrne, Nicolas Fagnoni, Eloy de Lera Acedo, Zara Abdurashidova, Tyrone Adams, James E. Aguirre, Paul Alexander, Zaki S. Ali, Rushelle Baartman, Yanga Balfour, Adam P. Beardsley, Gianni Bernardi, Tashalee S. Billings, Judd D. Bowman, Richard F. Bradley, Philip Bull, Jacob Burba, Steven Carey, Chris L. Carilli, Carina Cheng, David R. DeBoer, Matt Dexter, Nico Eksteen, John Ely, Aaron Ewall-Wice, Randall Fritz, Steven R. Furlanetto, Kingsley Gale-Sides, Brian Glendenning, Deepthi Gorthi, Bradley Greig, Jasper Grobbelaar, Ziyaad Halday, Jack Hickish, Daniel C. Jacobs, Austin Julius, MacCalvin Kariseb, Joshua Kerrigan, Piyanat Kittiwisit, Saul A. Kohn, Matthew Kolopanis, Adam Lanman, Paul La Plante, Adrian Liu, Anita Loots, Yin-zhe Ma, David Harold Edward MacMahon, Lourence Malan, Cresshim Malgas, Keith Malgas, Bradley Marero, Zachary E. Martinot, Andrei Mesinger, Mathakane Molewa, Tshegofalang Mosiane, Steven G. Murray, Abraham R. Neben, Bojan Nikolic, Hans Nuwegeld, Aaron R. Parsons, Nipanjana Patra, Samantha Pieterse, Jonathan C. Pober, Nima Razavi-Ghods, James Robnett, Kathryn Rosie, Peter Sims, Craig Smith, Hilton Swarts, Nithyanandan Thyagarajan, Pieter Van Van Wyngaarden, Peter K. G. Williams, Haoxuan Zheng. 2022-04-12. Direct Optimal Mapping for 21cm Cosmology: A Demonstration with the Hydrogen Epoch of Reionization Array. https://doi.org/10.3847/1538-4357%2Fac9053

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