Constraining isocurvature perturbations with the 21 cm emission from minihaloes

  title={Constraining isocurvature perturbations with the 21 cm emission from minihaloes},
  author={Yoshitaka Takeuchi and Sirichai Chongchitnan},
  journal={Monthly Notices of the Royal Astronomical Society},
We investigate the effects of isocurvature perturbations on the 21 cm radiation from minihaloes (MHs) at high redshifts and examine constraints on the isocurvature amplitude and power spectrum using the next generation of radio telescopes such as the Square Kilometre Array. We find that there is a realistic prospect of observing the isocurvature imprints in the 21 cm emission from MHs, but only if the isocurvature spectral index is close to 3 (i.e. the spectrum is blue). When the isocurvature… 

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