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Internal delensing of Cosmic Microwave Background polarization B-modes with the POLARBEAR experiment

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 نشر من قبل Giulio Fabbian
 تاريخ النشر 2019
  مجال البحث فيزياء
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Using only cosmic microwave background polarization data from the POLARBEAR experiment, we measure $B$-mode polarization delensing on subdegree scales at more than $5sigma$ significance. We achieve a 14% $B$-mode power variance reduction, the highest to date for internal delensing, and improve this result to 2% by applying for the first time an iterative maximum a posteriori delensing method. Our analysis demonstrates the capability of internal delensing as a means of improving constraints on inflationary models, paving the way for the optimal analysis of next-generation primordial $B$-mode experiments.



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