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arXiv · 1407.1247

Combining cosmological constraints from cluster counts and galaxy clustering

Fabien Lacasa
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Abstract

Present and future large scale surveys offer promising probes of cosmology. For example the Dark Energy Survey (DES) is forecast to detect ~300 millions galaxies and thousands clusters up to redshift ~1.3. I here show ongoing work to combine two probes of large scale structure : cluster number counts and galaxy 2-point function (in real or harmonic space). The halo model (coupled to a Halo Occupation Distribution) can be used to model the cross-covariance between these probes, and I introduce a diagrammatic method to compute easily the different terms involved. Furthermore, I compute the joint non-Gaussian likelihood, using the Gram-Charlier series. Then I show how to extend the methods of Bayesian hyperparameters to Poissonian distributions, in a first step to include them in this joint likelihood.

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Fabien Lacasa. 2014-07-04. Combining cosmological constraints from cluster counts and galaxy clustering. https://arxiv.org/abs/1407.1247

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