Direct Optimal Mapping for 21cm Cosmology: A Demonstration with the Hydrogen Epoch of Reionization Array
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.
Cite
@article{arxiv.2204.06021,
title = {Direct Optimal Mapping for 21cm Cosmology: A Demonstration with the Hydrogen Epoch of Reionization Array},
author = {Zhilei Xu and Jacqueline N. Hewitt and Kai-Feng Chen and Honggeun Kim and Joshua S. Dillon and Nicholas S. Kern and Miguel F. Morales and Bryna J. Hazelton and Ruby Byrne and Nicolas Fagnoni and Eloy de Lera Acedo and Zara Abdurashidova and Tyrone Adams and James E. Aguirre and Paul Alexander and Zaki S. Ali and Rushelle Baartman and Yanga Balfour and Adam P. Beardsley and Gianni Bernardi and Tashalee S. Billings and Judd D. Bowman and Richard F. Bradley and Philip Bull and Jacob Burba and Steven Carey and Chris L. Carilli and Carina Cheng and David R. DeBoer and Matt Dexter and Nico Eksteen and John Ely and Aaron Ewall-Wice and Randall Fritz and Steven R. Furlanetto and Kingsley Gale-Sides and Brian Glendenning and Deepthi Gorthi and Bradley Greig and Jasper Grobbelaar and Ziyaad Halday and Jack Hickish and Daniel C. Jacobs and Austin Julius and MacCalvin Kariseb and Joshua Kerrigan and Piyanat Kittiwisit and Saul A. Kohn and Matthew Kolopanis and Adam Lanman and Paul La Plante and Adrian Liu and Anita Loots and Yin-zhe Ma and David Harold Edward MacMahon and Lourence Malan and Cresshim Malgas and Keith Malgas and Bradley Marero and Zachary E. Martinot and Andrei Mesinger and Mathakane Molewa and Tshegofalang Mosiane and Steven G. Murray and Abraham R. Neben and Bojan Nikolic and Hans Nuwegeld and Aaron R. Parsons and Nipanjana Patra and Samantha Pieterse and Jonathan C. Pober and Nima Razavi-Ghods and James Robnett and Kathryn Rosie and Peter Sims and Craig Smith and Hilton Swarts and Nithyanandan Thyagarajan and Pieter Van Van Wyngaarden and Peter K. G. Williams and Haoxuan Zheng},
journal= {arXiv preprint arXiv:2204.06021},
year = {2022}
}
Comments
16 pages, 10 figures, 2 tables, published on ApJ