Constraints on fundamental cosmological parameters with upcoming redshifted 21 cm observations

Judd Bowman, Miguel F. Morales, Jacqueline N. Hewitt

Research output: Contribution to journalArticle

43 Citations (Scopus)

Abstract

Constraints on cosmological parameters from upcoming measurements with the Mileura Wide-field Array Low Frequency Demonstrator (MWA LFD) of the redshifted 21 cm power spectrum are forecasted assuming a flat ACDM cosmology and assuming that the reionization of neutral hydrogen in the intergalactic medium occurs below a redshift of z = 8. We find that observations with the MWA LFD cannot constrain the underlying cosmology in this scenario. In principle, a similar experiment with a 10-fold increase in collecting area could provide useful constraints on the slope of the inflationary power spectrum, ns, and the running of the spectral index, αs, but these constraints are subject to the caveat that even a small reionization contribution could be confused with the cosmological signal. In addition to the redshifted 21 cm signal, we include two nuisance components in our analysis related to the systematics and astrophysical foregrounds present in low-frequency radio observations. These components are found to be well separated from the signal and contribute little uncertainty (<30%) to the measured values of the cosmological model parameters.

Original languageEnglish (US)
Pages (from-to)1-9
Number of pages9
JournalAstrophysical Journal
Volume661
Issue number1 I
DOIs
StatePublished - May 20 2007
Externally publishedYes

Fingerprint

cosmology
low frequencies
power spectra
intergalactic media
radio observation
astrophysics
hydrogen
radio
slopes
fold
parameter
experiment
index
analysis
nuisance

Keywords

  • Early universe
  • Intergalactic medium
  • Radio lines: general
  • Techniques: interferometric

ASJC Scopus subject areas

  • Space and Planetary Science

Cite this

Constraints on fundamental cosmological parameters with upcoming redshifted 21 cm observations. / Bowman, Judd; Morales, Miguel F.; Hewitt, Jacqueline N.

In: Astrophysical Journal, Vol. 661, No. 1 I, 20.05.2007, p. 1-9.

Research output: Contribution to journalArticle

Bowman, Judd ; Morales, Miguel F. ; Hewitt, Jacqueline N. / Constraints on fundamental cosmological parameters with upcoming redshifted 21 cm observations. In: Astrophysical Journal. 2007 ; Vol. 661, No. 1 I. pp. 1-9.
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