Lensing Reconstruction using redshifted 21cm Fluctuations

Abstract

We investigate the potential of second generation measurements of redshifted 21 cm radiation from before and during the epoch of reionization (EOR) to reconstruct the matter density fluctuations along the line of sight. To do so we generalize the quadratic methods developed for the Cosmic Microwave Background (CMB) to 21 cm fluctuations. We show that the three dimensional signal can be decomposed into a finite number of line of sight Fourier modes that contribute to the lensing reconstruction. Our formalism properly takes account of correlations along the line of sight and uses all the information contained in quadratic combinations of the signal. In comparison with the CMB, 21 cm fluctuations have the disadvantage of a relatively scale invariant unlensed power spectrum which suppresses the lensing effect. The smallness of the lensing effect is compensated by using information from a range of observed redshifts. We estimate the size of experiments that are needed to measure this effect. With a square kilometer of collecting area and a maximal baseline of 3 km one can achieve lensing reconstruction noise levels an order of magnitude below CMB quadratic estimator constraints at L=1000, and map the deflection field out to less then a tenth of a degree (L> 2000) within a season of observations on one field. Statistical lensing power spectrum detections will be possible to sub-arcminute scales, even with the limited sky coverage that currently conceived experiments have. One should be able to improve constraints on cosmological parameters by using this method. With larger collecting areas or longer observing times, one could probe arcminute scales of the lensing potential and thus individual clusters. We address the effect that foregrounds might have on lensing reconstruction with 21 cm fluctuations.

14 pages, 8 Figures, replaced to match version to appear in ApJ

References in corpus (17)

• Wilkinson Microwave Anisotropy Probe (WMAP) Three Year Results: Implications for Cosmology
• Three Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Polarization Analysis
• Constraining the Evolution of the Ionizing Background and the Epoch of Reionization with z ~ 6 Quasars II: A Sample of 19 Quasars
• Cosmological Parameter Estimation Using 21 cm Radiation from the Epoch of Reionization
• The South Pole Telescope
• A Method for Separating the Physics from the Astrophysics of High-Redshift 21cm Fluctuations
• Twenty-one centimeter tomography with foregrounds
• Power Spectrum Sensitivity and the Design of Epoch of Reionization Observatories
• Improving Foreground Subtraction in Statistical Observations of 21 cm Emission from the Epoch of Reionization
• A Size of ~10 Mpc for the Ionized Bubbles at the End of Cosmic Reionization
• The influence of non-uniform reionization on the CMB
• Improved Constraints on The Neutral Intergalactic Hydrogen Surrounding Quasars at Redshifts z>6
• The EBEX Experiment
• Mapping dark matter with cosmic magnification
• Cosmic 21-cm Delensing of Microwave Background Polarization and the Minimum Detectable Energy Scale of Inflation
• Polarization of 21cm Radiation from the Epoch of Reionization
• Weak Gravitational Lensing of High-Redshift 21 cm Power Spectra

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