Bayesian Cosmic Web Reconstruction: BARCODE for Clusters

TL;DR

This paper introduces the Bayesian BARCODE method for reconstructing the Cosmic Web from galaxy cluster data, accounting for nonlinear constraints and redshift space distortions, validated through simulations.

Contribution

The paper presents a novel Bayesian formalism that reconstructs the Cosmic Web using galaxy clusters, incorporating nonlinear constraints and redshift space distortions.

Findings

Successful reconstruction of the Cosmic Web in simulations

Effective handling of redshift space distortions

Validation with simulated large-scale matter distribution

Abstract

We describe the Bayesian BARCODE formalism that has been designed towards the reconstruction of the Cosmic Web in a given volume on the basis of the sampled galaxy cluster distribution. Based on the realization that the massive compact clusters are responsible for the major share of the large scale tidal force field shaping the anisotropic and in particular filamentary features in the Cosmic Web. Given the nonlinearity of the constraints imposed by the cluster configurations, we resort to a state-of-the-art constrained reconstruction technique to find a proper statistically sampled realization of the original initial density and velocity field in the same cosmic region. Ultimately, the subsequent gravitational evolution of these initial conditions towards the implied Cosmic Web configuration can be followed on the basis of a proper analytical model or an N-body computer simulation. The BARCODE formalism includes an implicit treatment for redshift space distortions. This enables a direct reconstruction on the basis of observational data, without the need for a correction of redshift space artifacts. In this contribution we provide a general overview of the the Cosmic Web connection with clusters and a description of the Bayesian BARCODE formalism. We conclude with a presentation of its successful workings with respect to test runs based on a simulated large scale matter distribution, in physical space as well as in redshift space.