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Constraints on the growth of structure around cosmic voids in eBOSS DR14

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 نشر من قبل Adam Hawken
 تاريخ النشر 2019
  مجال البحث فيزياء
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We present catalogues of cosmic voids identified in the distribution of Luminous Red Galaxies (LRGs) and Quasi Stellar Objects (QSOs) in the fourteenth data release (DR14) of the extended Baryon Oscillation Spectroscopic Survey (eBOSS). We perform a multivariate analysis to assess the level of contamination in these catalogues by spurious Poisson underdensities. We find that the LRG void catalogue is largely free from contamination but that the QSO catalogue may be heavily contaminated. We analyse the multipoles of the void-galaxy cross-correlation function in these catalogues to obtain constraints on the growth rate of structure around voids. We find a value of $beta(z=0.703)=0.58^{+0.33}_{-0.28}$ for the LRG voids and $beta(z=1.53)=0.15^{+0.13}_{-0.12}$ for the QSO voids.

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