Real-space density profile reconstruction of stacked voids

TL;DR

This paper introduces a non-parametric, model-independent method to reconstruct the real-space density profiles of cosmic voids from observational data, avoiding redshift-space distortions and assumptions about cosmology.

Contribution

The paper presents a novel algorithm for reconstructing spherical density profiles of stacked voids in real space, validated with simulations and applied to SDSS data.

Findings

Successful reconstruction of void density profiles in simulations

First application to real SDSS void data

Method avoids redshift-space distortions and cosmological assumptions

Abstract

We present a non-parametric, model-independent method to reconstruct the spherical density profiles of void stacks in real space, without redshift-space distortions. Our method uses the expected spherical symmetry of stacked voids to build the shape of the spherical density profile of cosmic voids in real space without any assumption about the cosmological model. We test the reconstruction algorithm with both a toy model and a full dark matter simulation. We present the result for the simulation: the reconstruction of the spherical density profile for a simulated stacked void in real space. We also present a first application of the algorithm to reconstruct real cosmic void stacks density profiles in real space from the Sloan Digital Sky Survey (Sutter et al. 2012b). We discuss capabilities of the algorithm and possible future improvements. Reconstructed density profiles from real voids open the way to the study of the spherically averaged dynamical structure of voids.