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arXiv · 2606.13538

A local Universe catalogue of structures and voids dynamically identified using Cosmic-Flows4++ZOA peculiar velocities

A. M. Hollinger·H. M. Courtois
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Abstract

Cosmic voids and superclusters are among the largest structures in the Universe and provide complementary probes of the growth of large-scale structure and the underlying gravitational field. We present a comprehensive catalogue of the main local Universe cosmic web voids and knots, using the updated CosmicFlows-4++ Zone of Avoidance (CF4++ZOA) catalogue out to redshift z=0.1. To do this we use the V-web algorithm which provides a dynamically motivated map of the the local cosmic web, tracing the major expanding and converging regions of the local Universe. The robustness of the catalogue is assessed using the ensemble of Hamiltonian Monte Carlo realizations of the CF4++ZOA reconstruction. We additionally remove any structure that exceeds the survey boundaries and present catalogues of 37 voids and 42 knot regions within the reconstructed survey volume. The identified emptying regions (voids) have effective radii ranging from 13 to 38 h-1Mpc. The high density converging regions (knots) have volumes ranging from 10^4 to 3.3x10^5 h-3 Mpc^3.

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A. M. Hollinger, H. M. Courtois. 2026-06-11. A local Universe catalogue of structures and voids dynamically identified using Cosmic-Flows4++ZOA peculiar velocities. https://arxiv.org/abs/2606.13538

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