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تسجيل مستخدم جديدComparison of the linear bias models in the light of the Dark Energy Survey
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The evolution of the linear and scale independent bias, based on the most popular dark matter bias models within the $Lambda$CDM cosmology, is confronted to that of the Dark Energy Survey (DES) Luminous Red Galaxies (LRGs). Applying a $chi^2$ minimization procedure between models and data we find that all the considered linear bias models reproduce well the LRG bias data. The differences among the bias models are absorbed in the predicted mass of the dark-matter halo in which LRGs live and which ranges between $sim 6 times 10^{12} h^{-1} M_{odot}$ and $1.4 times 10^{13} h^{-1} M_{odot}$, for the different bias models. Similar results, reaching however a maximum value of $sim 2times 10^{13} h^{-1} M_{odot}$, are found by confronting the SDSS (2SLAQ) Large Red Galaxies clustering with theoretical clustering models, which also include the evolution of bias. This later analysis also provides a value of $Omega_{m}=0.30pm 0.01$, which is in excellent agreement with recent joint analyses of different cosmological probes and the reanalysis of the Planck data.
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