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arXiv · 1909.11733

Mitigating Internal Instrument Coupling II: A Method Demonstration with the Hydrogen Epoch of Reionization Array

Nicholas S. Kern·Aaron R. Parsons·Joshua S. Dillon·Adam E. Lanman·Adrian Liu·Philip Bull·Aaron Ewall-Wice·Zara Abdurashidova·James E. Aguirre·Paul Alexander·Zaki S. Ali·Yanga Balfour·Adam P. Beardsley·Gianni Bernardi·Judd D. Bowman·Richard F. Bradley·Jacob Burba·Chris L. Carilli·Carina Cheng·David R. DeBoer·Matt Dexter·Eloy de Lera Acedo·Nicolas Fagnoni·Randall Fritz·Steve R. Furlanetto·Brian Glendenning·Deepthi Gorthi·Bradley Greig·Jasper Grobbelaar·Ziyaad Halday·Bryna J. Hazelton·Jacqueline N. Hewitt·Jack Hickish·Daniel C. Jacobs·Austin Julius·Joshua Kerrigan·Piyanat Kittiwisit·Saul A. Kohn·Matthew Kolopanis·Paul La Plante·Telalo Lekalake·David MacMahon·Lourence Malan·Cresshim Malgas·Matthys Maree·Zachary E. Martinot·Eunice Matsetela·Andrei Mesinger·Mathakane Molewa·Miguel F. Morales·Tshegofalang Mosiane·Steven G. Murray·Abraham R. Neben·Nipanjana Patra·Samantha Pieterse·Jonathan C. Pober·Nima Razavi-Ghods·Jon Ringuette·James Robnett·Kathryn Rosie·Peter Sims·Craig Smith·Angelo Syce·Nithyanandan Thyagarajan·Peter K. G. Williams·Haoxuan Zheng
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Abstract

We present a study of internal reflection and cross coupling systematics in Phase I of the Hydrogen Epoch of Reionization Array (HERA). In a companion paper, we outlined the mathematical formalism for such systematics and presented algorithms for modeling and removing them from the data. In this work, we apply these techniques to data from HERA's first observing season as a method demonstration. The data show evidence for systematics that, without removal, would hinder a detection of the 21 cm power spectrum for the targeted EoR line-of-sight modes in the range 0.2 < k_parallel < 0.5\ h^-1 Mpc. After systematic removal, we find we can recover these modes in the power spectrum down to the integrated noise-floor of a nightly observation, achieving a dynamic range in the EoR window of 10^-6 in power (mK^2 units) with respect to the bright galactic foreground signal. In the absence of other systematics and assuming the systematic suppression demonstrated here continues to lower noise levels, our results suggest that fully-integrated HERA Phase I may have the capacity to set competitive upper limits on the 21 cm power spectrum. For future observing seasons, HERA will have upgraded analog and digital hardware to better control these systematics in the field.

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Nicholas S. Kern, Aaron R. Parsons, Joshua S. Dillon, Adam E. Lanman, Adrian Liu, Philip Bull, Aaron Ewall-Wice, Zara Abdurashidova, James E. Aguirre, Paul Alexander, Zaki S. Ali, Yanga Balfour, Adam P. Beardsley, Gianni Bernardi, Judd D. Bowman, Richard F. Bradley, Jacob Burba, Chris L. Carilli, Carina Cheng, David R. DeBoer, Matt Dexter, Eloy de Lera Acedo, Nicolas Fagnoni, Randall Fritz, Steve R. Furlanetto, Brian Glendenning, Deepthi Gorthi, Bradley Greig, Jasper Grobbelaar, Ziyaad Halday, Bryna J. Hazelton, Jacqueline N. Hewitt, Jack Hickish, Daniel C. Jacobs, Austin Julius, Joshua Kerrigan, Piyanat Kittiwisit, Saul A. Kohn, Matthew Kolopanis, Paul La Plante, Telalo Lekalake, David MacMahon, Lourence Malan, Cresshim Malgas, Matthys Maree, Zachary E. Martinot, Eunice Matsetela, Andrei Mesinger, Mathakane Molewa, Miguel F. Morales, Tshegofalang Mosiane, Steven G. Murray, Abraham R. Neben, Nipanjana Patra, Samantha Pieterse, Jonathan C. Pober, Nima Razavi-Ghods, Jon Ringuette, James Robnett, Kathryn Rosie, Peter Sims, Craig Smith, Angelo Syce, Nithyanandan Thyagarajan, Peter K. G. Williams, Haoxuan Zheng. 2019-09-25. Mitigating Internal Instrument Coupling II: A Method Demonstration with the Hydrogen Epoch of Reionization Array. https://doi.org/10.3847/1538-4357/ab5e8a

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