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A study of fundamental limitations to statistical detection of redshifted H i from the epoch of reionization

journal contribution
posted on 2023-05-17, 21:35 authored by Thyagarajan, N, Udaya Shankar, N, Subrahmanyan, R, Arcus, W, Bernardi, G, Bowman, JD, Briggs, F, Bunton, JD, Cappallo, RJ, Corey, BE, Desouza, L, Emrich, D, Gaensler, BM, Goeke, RF, Greenhill, LJ, Hazelton, BJ, Herne, D, Hewitt, JN, Johnston-Hollitt, M, Kaplan, DL, Kasper, JC, Kincaid, BB, Koenig, R, Kratzenberg, E, Lonsdale, CJ, Lynch, MJ, McWhirter, SR, Mitchell, DA, Morales, MF, Morgan, EH, Oberoi, D, Ord, SM, Pathikulangara, J, Remillard, RA, Rogers, AEE, Roshi, DA, Salah, JE, Sault, RJ, Srivani, KS, Stevens, JB, Thiagaraj, P, Tingay, SJ, Wayth, RB, Waterson, M, Webster, RL, Whitney, AR, Williams, AJ, Williams, CL, Wyithe, JSB
In this paper, we explore for the first time the relative magnitudes of three fundamental sources of uncertainty, namely, foreground contamination, thermal noise, and sample variance, in detecting the H I power spectrum from the epoch of reionization (EoR). We derive limits on the sensitivity of a Fourier synthesis telescope to detect EoR based on its array configuration and a statistical representation of images made by the instrument. We use the Murchison Widefield Array (MWA) configuration for our studies. Using a unified framework for estimating signal and noise components in the H I power spectrum, we derive an expression for and estimate the contamination from extragalactic point-like sources in three-dimensional k-space. Sensitivity for EoR H I power spectrum detection is estimated for different observing modes with MWA. With 1000 hr of observing on a single field using the 128 tile MWA, EoR detection is feasible (S/N >1 for k ≲ 0.8 Mpc-1). Bandpass shaping and refinements to the EoR window are found to be effective in containing foreground contamination, which makes the instrument tolerant to imaging errors. We find that for a given observing time, observing many independent fields of view does not offer an advantage over a single field observation when thermal noise dominates over other uncertainties in the derived power spectrum.

History

Publication title

Astrophysical Journal

Volume

776

Article number

6

Number

6

Pagination

1-17

ISSN

0004-637X

Department/School

School of Natural Sciences

Publisher

Univ Chicago Press

Place of publication

1427 E 60Th St, Chicago, USA, Il, 60637-2954

Rights statement

Copyright 2013 The American Astronomical Society

Repository Status

  • Restricted

Socio-economic Objectives

Expanding knowledge in the physical sciences