The VIMOS Public Extragalactic Redshift Survey - Searching for Cosmic Voids

TL;DR

This paper develops a new method to identify and characterize cosmic voids in galaxy surveys, providing insights into large-scale structure and cosmology at intermediate redshifts.

Contribution

A novel void search technique based on empty spheres that accounts for survey boundaries and gaps, validated with mock catalogues and applied to VIPERS data.

Findings

Void size distribution matches mock catalogues

Void-galaxy correlation indicates outflow velocities

Constructed a comprehensive void catalogue for VIPERS

Abstract

The characterisation of cosmic voids gives unique information about the large-scale distribution of galaxies, their evolution and the cosmological model. We identify and characterise cosmic voids in the VIMOS Public Extragalactic Redshift Survey (VIPERS) at redshift 0.55 < z < 0.9. A new void search method is developed based upon the identification of empty spheres that fit between galaxies. The method can be used to characterise the cosmic voids despite the presence of complex survey boundaries and internal gaps. We investigate the impact of systematic observational effects and validate the method against mock catalogues. We measure the void size distribution and the void-galaxy correlation function. We construct a catalogue of voids in VIPERS. The distribution of voids is found to agree well with the distribution of voids found in mock catalogues. The void-galaxy correlation function shows indications of outflow velocity from the voids.