The dark matter of galaxy voids

Abstract

How do observed voids relate to the underlying dark matter distribution? To examine the spatial distribution of dark matter contained within voids identified in galaxy surveys, we apply Halo Occupation Distribution models representing sparsely and densely sampled galaxy surveys to a high-resolution N-body simulation. We compare these galaxy voids to voids found in the halo distribution, low-resolution dark matter, and high-resolution dark matter. We find that voids at all scales in densely sampled surveys - and medium- to large-scale voids in sparse surveys - trace the same underdensities as dark matter, but they are larger in radius by ~20%, they have somewhat shallower density profiles, and they have centers offset by ~0.4Rv rms. However, in void-to-void comparison we find that shape estimators are less robust to sampling, and the largest voids in sparsely sampled surveys suffer fragmentation at their edges. We find that voids in galaxy surveys always correspond to underdensities in the dark matter, though the centers may be offset. When this offset is taken into account, we recover almost identical radial density profiles between galaxies and dark matter. All mock catalogs used in this work are available at http://www.cosmicvoids.net.

12 pages, 8 figures, minor changes, MNRAS accepted

References in corpus (5)

• Transients from Initial Conditions in Cosmological Simulations
• Galaxy Evolution from Halo Occupation Distribution Modeling of DEEP2 and SDSS Galaxy Clustering
• ZOBOV: a parameter-free void-finding algorithm
• The darkness that shaped the void: dark energy and cosmic voids
• The BigBOSS Experiment

Cited by in corpus (36)

• Testing Gravity using Cosmic Voids
• Massive Neutrinos Leave Fingerprints on Cosmic Voids
• Probing cosmology and gravity with redshift-space distortions around voids
• A measurement of the Alcock-Paczynski effect using cosmic voids in the SDSS
• Lensing Measurements of the Mass Distribution in SDSS Voids
• Dark Sky Simulations: Early Data Release
• Large-Scale Clustering of Cosmic Voids
• On the linearity of tracer bias around voids
• More out of less: an excess integrated Sachs-Wolfe signal from supervoids mapped out by the Dark Energy Survey
• Void Lensing as a Test of Gravity
• Imprint of DES super-structures on the Cosmic Microwave Background
• The part and the whole: voids, supervoids, and their ISW imprint
• Dark matter voids in the SDSS galaxy survey
• The view from the boundary: a new void stacking method
• The life and death of cosmic voids
• Voids in cosmological simulations over cosmic time
• Cosmic voids detection without density measurements
• A Correlation Between Hard Gamma-ray Sources and Cosmic Voids Along the Line of Sight
• On the observability of coupled dark energy with cosmic voids
• The halo bias inside cosmic voids
• Cold imprint of supervoids in the Cosmic Microwave Background re-considered with Planck and BOSS DR10
• Cosmological parameter constraints from CMB lensing with cosmic voids
• The Galaxy Population In Voids: Are All Voids The Same?
• Identification of Cosmic Voids as Massive Cluster Counterparts
• The Local Void: for or against LCDM?
• On the Merger Rate of Primordial Black Holes in Cosmic Voids
• On the Abundance of Extreme Voids
• Evolution of density and velocity profiles of dark matter and dark energy in spherical voids
• Effects of dark matter pressure on the ellipticity of cosmic voids
• The galaxy bias profile of cosmic voids
• Bayesian large-scale structure inference and cosmic web analysis
• An integrated Sachs-Wolfe effect vs redshift test for the cosmological parameters
• VIDE: The Void IDentification and Examination toolkit
• Stochastic Order Redshift Technique (SORT): a simple, efficient and robust method to improve cosmological redshift measurements
• Tensor anisotropy as a tracer of cosmic voids
• Answers from the void: VIDE and its applications