Absolute Calibration Strategies for the Hydrogen Epoch of Reionization Array and Their Impact on the 21 cm Power Spectrum

Journal
Date Issued
2020
Author(s)
Kern, Nicholas S.
•
Dillon, Joshua S.
•
Parsons, Aaron R.
•
Carilli, Christopher L.
•
•
Abdurashidova, Zara
•
Aguirre, James E.
•
Alexander, Paul
•
Ali, Zaki S.
•
Balfour, Yanga
•
Beardsley, Adam P.
•
Billings, Tashalee S.
•
Bowman, Judd D.
•
Bradley, Richard F.
•
•
Burba, Jacob
•
Carey, Steven
•
Cheng, Carina
•
DeBoer, David R.
•
Dexter, Matt
•
de Lera Acedo, Eloy
•
Ely, John
•
Ewall-Wice, Aaron
•
Fagnoni, Nicolas
•
Fritz, Randall
•
Furlanetto, Steve R.
•
Gale-Sides, Kingsley
•
Glendenning, Brian
•
Gorthi, Deepthi
•
Greig, Bradley
•
Grobbelaar, Jasper
•
Halday, Ziyaad
•
Hazelton, Bryna J.
•
Hewitt, Jacqueline N.
•
Hickish, Jack
•
Jacobs, Daniel C.
•
Julius, Austin
•
Kerrigan, Joshua
•
Kittiwisit, Piyanat
•
Kohn, Saul A.
•
Kolopanis, Matthew
•
Lanman, Adam
•
La Plante, Paul
•
Lekalake, Telalo
•
Liu, Adrian
•
MacMahon, David
•
Malan, Lourence
•
Malgas, Cresshim
•
Maree, Matthys
•
Martinot, Zachary E.
•
Matsetela, Eunice
•
•
Molewa, Mathakane
•
Morales, Miguel F.
•
Mosiane, Tshegofalang
•
Murray, Steven G.
•
Neben, Abraham R.
•
Nikolic, Bojan
•
Nunhokee, Chuneeta D.
•
Patra, Nipanjana
•
Pieterse, Samantha
•
Pober, Jonathan C.
•
Razavi-Ghods, Nima
•
Ringuette, Jon
•
Robnett, James
•
Rosie, Kathryn
•
Sims, Peter
•
Smith, Craig
•
Syce, Angelo
•
Thyagarajan, Nithyanandan
•
Williams, Peter K. G.
•
Zheng, Haoxuan
DOI
Abstract
We discuss absolute calibration strategies for Phase I of the Hydrogen Epoch of Reionization Array (HERA), which aims to measure the cosmological 21 cm signal from the Epoch of Reionization. HERA is a drift-scan array with a 10° wide field of view, meaning bright, well-characterized point-source transits are scarce. This, combined with HERA's redundant sampling of the uv plane and the modest angular resolution of the Phase I instrument, make traditional sky-based and self-calibration techniques difficult to implement with high dynamic range. Nonetheless, in this work, we demonstrate calibration for HERA using point-source catalogs and electromagnetic simulations of its primary beam. We show that unmodeled diffuse flux and instrumental contaminants can corrupt the gain solutions and present a gain-smoothing approach for mitigating their impact on the 21 cm power spectrum. We also demonstrate a hybrid sky and redundant calibration scheme and compare it to pure sky-based calibration, showing only a marginal improvement to the gain solutions at intermediate delay scales. Our work suggests that the HERA Phase I system can be well calibrated for a foreground avoidance power spectrum estimator by applying direction-independent gains with a small set of degrees of freedom across the frequency and time axes.
Volume
890
Issue
2
Start page
122
Uri
Url
Issn Identifier
0004-637X
Ads BibCode
2020ApJ...890..122K
Rights
open.access
File(s)
Loading...
Thumbnail Image
Name

kern20b_archive.pdf

Description
postprint
Size

8.21 MB

Format

Adobe PDF

Checksum (MD5)

4d88e34d72cf2d8f360df01c93a8fd2b