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تسجيل مستخدم جديدUsing the Marked Power Spectrum to Detect the Signature of Neutrinos in Large-Scale Structure
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Cosmological neutrinos have their greatest influence in voids: these are the regions with the highest neutrino to dark matter density ratios. The marked power spectrum can be used to emphasize low density regions over high density regions, and therefore is potentially much more sensitive than the power spectrum to the effects of neutrino masses. Using 22,000 N-body simulations from the Quijote suite, we quantify the information content in the marked power spectrum of the matter field, and show that it outperforms the standard power spectrum by setting constraints improved by a factor larger than 2 on all cosmological parameters. The combination of marked and standard power spectrum allows to place a 4.3{sigma} constraint on the minimum sum of the neutrino masses with a volume equal to 1 (Gpc/h)^3 and without CMB priors. Combinations of different marked power spectra yield a 6{sigma} constraint within the same conditions.
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