Lensing of 21-cm absorption haloes of z∼ 2-30 first galaxies
نویسندگان
چکیده
منابع مشابه
Lensing of 21cm Absorption “Halos” of z ∼20-30 First Galaxies
Extended 21cm absorption regions (dubbed “21cm absorption halos”) around first galaxies at z ∼ 30 are likely the first distinctive structures accessible to radio observations. Though the radio array capable of detecting and resolving them must have ∼ 200 km total collecting area, given the great impact of such detections to the understanding of the reionization process and cosmology, such radio...
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We study the limits of accuracy for weak lensing maps of dark matter using diffuse 21-cm radiation from the pre-reionization epoch using simulations. We improve on previous “optimal” quadratic lensing estimators by using shear and convergence instead of deflection angles. We find that non-Gaussianity provides a limit to the accuracy of weak lensing reconstruction, even if instrumental noise is ...
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We investigate the potential of second generation measurements of redshifted 21 cm radiation from 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. The three dimensional signal can be analyzed into a finite number of line o...
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 2007
ISSN: 0035-8711
DOI: 10.1111/j.1365-2966.2007.12090.x