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arXiv · 2311.10711

Direct Optimal Mapping Image Power Spectrum and its Window Functions

Zhilei Xu·Honggeun Kim·Jacqueline N. Hewitt·Kai-Feng Chen·Nicholas S. Kern·Eleanor Rath·Ruby Byrne·Adélie Gorce·Robert Pascua·Zachary E. Martinot·Joshua S. Dillon·Bryna J. Hazelton·Adrian Liu·Miguel F. Morales·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·Eloy de Lera Acedo·Matt Dexter·Nico Eksteen·John Ely·Aaron Ewall-Wice·Nicolas Fagnoni·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·Anita Loots·David Harold Edward MacMahon·Lourence Malan·Cresshim Malgas·Keith Malgas·Bradley Marero·Andrei Mesinger·Mathakane Molewa·Tshegofalang Mosiane·Steven G. Murray·Abraham R. Neben·Bojan Nikolic·Hans Nuwegeld·Aaron R. Parsons·Nipanjana Patra·Samantha Pieterse·Nima Razavi-Ghods·James Robnett·Kathryn Rosie·Peter Sims·Craig Smith·Hilton Swarts·Nithyanandan Thyagarajan·Pieter van Wyngaarden·Peter K. G. Williams·Haoxuan Zheng
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Abstract

The key to detecting neutral hydrogen during the epoch of reionization (EoR) is to separate the cosmological signal from the dominating foreground radiation. We developed direct optimal mapping (DOM) to map interferometric visibilities; it contains only linear operations, with full knowledge of point spread functions from visibilities to images. Here, we demonstrate a fast Fourier transform-based image power spectrum and its window functions computed from the DOM images. We use noiseless simulation, based on the Hydrogen Epoch of Reionization Array Phase I configuration, to study the image power spectrum properties. The window functions show $<10^{-11}$ of the integrated power leaks from the foreground-dominated region into the EoR window; the 2D and 1D power spectra also verify the separation between the foregrounds and the EoR.

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Zhilei Xu, Honggeun Kim, Jacqueline N. Hewitt, Kai-Feng Chen, Nicholas S. Kern, Eleanor Rath, Ruby Byrne, Adélie Gorce, Robert Pascua, Zachary E. Martinot, Joshua S. Dillon, Bryna J. Hazelton, Adrian Liu, Miguel F. Morales, 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, Eloy de Lera Acedo, Matt Dexter, Nico Eksteen, John Ely, Aaron Ewall-Wice, Nicolas Fagnoni, 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, Anita Loots, David Harold Edward MacMahon, Lourence Malan, Cresshim Malgas, Keith Malgas, Bradley Marero, Andrei Mesinger, Mathakane Molewa, Tshegofalang Mosiane, Steven G. Murray, Abraham R. Neben, Bojan Nikolic, Hans Nuwegeld, Aaron R. Parsons, Nipanjana Patra, Samantha Pieterse, Nima Razavi-Ghods, James Robnett, Kathryn Rosie, Peter Sims, Craig Smith, Hilton Swarts, Nithyanandan Thyagarajan, Pieter van Wyngaarden, Peter K. G. Williams, Haoxuan Zheng. 2024-07-06. Direct Optimal Mapping Image Power Spectrum and its Window Functions. https://arxiv.org/abs/2311.10711

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