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Title: BRIGHT SOURCE SUBTRACTION REQUIREMENTS FOR REDSHIFTED 21 cm MEASUREMENTS

Abstract

The H I 21 cm transition line is expected to be an important probe into the cosmic dark ages and epoch of reionization. Foreground source removal is one of the principal challenges for the detection of this signal. This paper investigates the extragalactic point source contamination and how accurately bright sources ({approx}>1 Jy) must be removed in order to detect 21 cm emission with upcoming radio telescopes such as the Murchison Widefield Array. We consider the residual contamination in 21 cm maps and power spectra due to position errors in the sky model for bright sources, as well as frequency-independent calibration errors. We find that a source position accuracy of 0.1 arcsec will suffice for detection of the H I power spectrum. For calibration errors, 0.05% accuracy in antenna gain amplitude is required in order to detect the cosmic signal. Both sources of subtraction error produce residuals that are localized to small angular scales, k{sub perpendicular} {approx}> 0.05 Mpc{sup -1}, in the two-dimensional power spectrum.

Authors:
 [1];  [2];  [3]
  1. New Mexico Tech, Socorro, NM 87801 (United States)
  2. California Institute of Technology, Pasadena, CA 91125 (United States)
  3. National Radio Astronomy Observatory, Socorro, NM 87801 (United States)
Publication Date:
OSTI Identifier:
21471175
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal
Additional Journal Information:
Journal Volume: 724; Journal Issue: 1; Other Information: DOI: 10.1088/0004-637X/724/1/526; Journal ID: ISSN 0004-637X
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTROPHYSICS; CALIBRATION; DATA ANALYSIS; POINT SOURCES; RADIO TELESCOPES; RED SHIFT; SIGNALS; UNIVERSE; ANTENNAS; ELECTRICAL EQUIPMENT; ELECTRONIC EQUIPMENT; EQUIPMENT; PHYSICS; RADIATION SOURCES; RADIO EQUIPMENT; TELESCOPES

Citation Formats

Datta, A., Bowman, J. D., and Carilli, C. L., E-mail: adatta@nrao.ed. BRIGHT SOURCE SUBTRACTION REQUIREMENTS FOR REDSHIFTED 21 cm MEASUREMENTS. United States: N. p., 2010. Web. doi:10.1088/0004-637X/724/1/526.
Datta, A., Bowman, J. D., & Carilli, C. L., E-mail: adatta@nrao.ed. BRIGHT SOURCE SUBTRACTION REQUIREMENTS FOR REDSHIFTED 21 cm MEASUREMENTS. United States. doi:10.1088/0004-637X/724/1/526.
Datta, A., Bowman, J. D., and Carilli, C. L., E-mail: adatta@nrao.ed. Sat . "BRIGHT SOURCE SUBTRACTION REQUIREMENTS FOR REDSHIFTED 21 cm MEASUREMENTS". United States. doi:10.1088/0004-637X/724/1/526.
@article{osti_21471175,
title = {BRIGHT SOURCE SUBTRACTION REQUIREMENTS FOR REDSHIFTED 21 cm MEASUREMENTS},
author = {Datta, A. and Bowman, J. D. and Carilli, C. L., E-mail: adatta@nrao.ed},
abstractNote = {The H I 21 cm transition line is expected to be an important probe into the cosmic dark ages and epoch of reionization. Foreground source removal is one of the principal challenges for the detection of this signal. This paper investigates the extragalactic point source contamination and how accurately bright sources ({approx}>1 Jy) must be removed in order to detect 21 cm emission with upcoming radio telescopes such as the Murchison Widefield Array. We consider the residual contamination in 21 cm maps and power spectra due to position errors in the sky model for bright sources, as well as frequency-independent calibration errors. We find that a source position accuracy of 0.1 arcsec will suffice for detection of the H I power spectrum. For calibration errors, 0.05% accuracy in antenna gain amplitude is required in order to detect the cosmic signal. Both sources of subtraction error produce residuals that are localized to small angular scales, k{sub perpendicular} {approx}> 0.05 Mpc{sup -1}, in the two-dimensional power spectrum.},
doi = {10.1088/0004-637X/724/1/526},
journal = {Astrophysical Journal},
issn = {0004-637X},
number = 1,
volume = 724,
place = {United States},
year = {2010},
month = {11}
}