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Reconstructing large scales at cosmic dawn

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 نشر من قبل Selim Hotinli
 تاريخ النشر 2020
  مجال البحث فيزياء
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The cosmic microwave background (CMB) serves as a backlight to large-scale structure during the epoch of reionization, where Thomson scattering gives rise to temperature anisotropies on small angular scales from the kinetic Sunyaev Zeldovich (kSZ) effect. In this paper, we demonstrate that the technique of kSZ tomography (velocity reconstruction), based on cross correlations between CMB temperature and 21cm surveys, can significantly improve constraints on models of inhomogeneous reionization and provide information about large-scale modes that are poorly characterized by 21cm measurements themselves due to foreground contamination.



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