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Cluster Counts Tension : a Sign of Primordial Non-Gaussianity ?

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 نشر من قبل Ziad Sakr
 تاريخ النشر 2018
  مجال البحث فيزياء
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Evolution and abundance of the large-scale structures we observe today, such as clusters of galaxies, is sensitive to the statistical properties of dark matter primordial density fluctuations, which is assumed to follow a Gaussian probability distribution function. Within this assumption, a significant disagreement have been found between clusters counts made by Planck and their prediction when calibrated by CMB angular power spectrum. The purpose of this work is to relax the Gaussianty assumption and test if Non-Gaussianity in dark matter primordial density fluctuations, could alleviate the tension.



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