A STUDY OF FUNDAMENTAL LIMITATIONS TO STATISTICAL DETECTION OF REDSHIFTED H I FROM THE EPOCH OF REIONIZATION

Journal Article · Thu Oct 10 00:00:00 EDT 2013 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/776/1/6· OSTI ID:22270885

Thyagarajan, Nithyanandan; Udaya Shankar, N.; Subrahmanyan, Ravi ^[1]; Arcus, Wayne; Emrich, David; Herne, David ^[2]; Bernardi, Gianni; Greenhill, Lincoln J. ^[3]; Bowman, Judd D. ^[4]; Briggs, Frank; Gaensler, Bryan M. ^[5]; Bunton, John D.; DeSouza, Ludi ^[6]; Cappallo, Roger J.; Corey, Brian E. ^[7]; Goeke, Robert F.; Hewitt, Jacqueline N. ^[8]; Hazelton, Bryna J. ^[9]; Johnston-Hollitt, Melanie ^[10]; others, and

---

1. Raman Research Institute, Bangalore (India)
2. Curtin University, Perth (Australia)
3. Harvard-Smithsonian Center for Astrophysics, Cambridge (United States)
4. Arizona State University, Tempe, AZ (United States)
5. ARC Centre of Excellence for All-sky Astrophysics (CAASTRO), Sydney (Australia)
6. CSIRO Astronomy and Space Science, NSW (Australia)
7. MIT Haystack Observatory, Westford, MA (United States)
8. MIT Kavli Institute for Astrophysics and Space Research, Cambridge, MA (United States)
9. University of Washington, Seattle, WA (United States)
10. Victoria University of Wellington, Wellington (New Zealand)

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{sup –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.

• OSTI ID: 22270885
• Journal Information: Astrophysical Journal, Vol. 776, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ASTRONOMY
ASTROPHYSICS
DETECTION
ENERGY SPECTRA
GALAXIES
HYDROGEN
NOISE
RED SHIFT
SENSITIVITY
SPACE
STARS
TELESCOPES
UNIVERSE