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arXiv · 2610.18348

Structure and evolution of cosmic voids within DESI DR1

Óscar Monllor-Berbegal·Susana Planelles·Vicent Quilis
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Abstract

Ongoing stage IV galaxy surveys such as DESI or Euclid offer an unprecedented amount of information to study the large-scale structure of the Universe by mapping tens of millions of galaxies. Within the context of cosmic voids, already released and future catalogues will help better understand the void structure and evolution as well as the cosmological model constraints derived from their statistics. With the recent DESI Data Release 1, our aim is to obtain a new void catalogue that allows us to study the properties of cosmic voids at different redshifts, hence providing insight not only on their structure but also on their evolution. We select the DESI BGS and LRG samples for this study. Before the void-finding process, the data goes through a preprocessing pipeline tackling redshift space distortions and reconstructing the mildly non-linear velocity field. After that, the new AVISM void finder is applied to the preprocessed data, obtaining two void catalogues in different redshift bins (0.1 < z < 0.3 and 0.4 < z < 0.8), both within a 1400^3 cMpc^3 cube. We successfully recover N_BGS = 1114 and N_LRG = 216 clean voids with sizes up to ~ 65 cMpc. The void size function, 3D shape variables, density profiles, and linear bias are obtained and analysed. Both the size function and the density profiles obtained are in agreement with previous theoretical studies. The expected mass depletion in void evolution is shown by the evolution of density profiles. We obtain a roughly constant linear bias inside r < Re with mean values of 1.31 +/- 0.02 and 2.14 +/- 0.04 for BGS and LRG, respectively. Both void catalogues are publicly released.

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Óscar Monllor-Berbegal, Susana Planelles, Vicent Quilis. 2026-10-13. Structure and evolution of cosmic voids within DESI DR1. https://arxiv.org/abs/2610.18348

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