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Robust Intensity Mapping Analysis against Foregrounds for the Epoch of Reionization

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 نشر من قبل Yi Mao
 تاريخ النشر 2020
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Meng Zhou -




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Intensity mapping of the HI 21 cm line and the CO 2.61 mm line from the epoch of reionization has emerged as powerful, complementary, probes of the high-redshift Universe. However, both maps and their cross-correlation are dominated by foregrounds. We propose a new analysis by which the signal is unbiased by foregrounds, i.e. it can be measured without foreground mitigation. We construct the antisymmetric part of the HI-CO cross-correlation, arising because the statistical fluctuations of two fields have different evolution in time. We show that the sign of this new signal can distinguish model-independently whether inside-out reionization happens during some interval of time.



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