Deep Extragalactic VIsible Legacy Survey (DEVILS): Galaxy group catalogue for the D10-COSMOS field with 90% spectroscopic redshift completeness

Matías Bravo; Luke J. M. Davies; Aaron S. G. Robotham; Claudia del P. Lagos; Sabine Bellstedt; Joss Bland-Hawthorn; Malgorzata Siudek; Trystan S. Lambert; Chris Power

arXiv · 2509.13530

Deep Extragalactic VIsible Legacy Survey (DEVILS): Galaxy group catalogue for the D10-COSMOS field with 90% spectroscopic redshift completeness

Matías Bravo·Luke J. M. Davies·Aaron S. G. Robotham·Claudia del P. Lagos·Sabine Bellstedt·Joss Bland-Hawthorn·Malgorzata Siudek·Trystan S. Lambert·Chris Power

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Abstract

Large-scale galaxy redshift surveys conducted over the last couple of decades have proven crucial in deepening our understanding of structure growth in the Universe and galaxy evolution. While there have been several such surveys, until now those that achieve the high completeness and precision necessary to probe the low-mass end of galaxy groups have been limited to relatively low redshifts ($z\lesssim0.3$), with surveys exploring the more distant Universe being constrained by small sample sizes and/or low redshift completeness. The recent Deep Extragalactic VIsible Legacy Survey (DEVILS) aims to explore galaxy environment over the last $\sim6$ Gyr with a completeness level comparable to the most complete local Universe surveys ($>85\%$). In this work, we present the galaxy group catalogue for the D10-COSMOS field from DEVILS, which achieves a redshift completeness of $90\%$ for galaxies with $Y<21.2$ mag. We showcase the science potential by exploring the impact of environment on the fraction and power of active galactic nuclei (AGN), finding that satellites in galaxy groups show no evidence of altered AGN properties, while satellites in clusters exhibit increased AGN fractions but decreased AGN luminosities.

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Matías Bravo, Luke J. M. Davies, Aaron S. G. Robotham, Claudia del P. Lagos, Sabine Bellstedt, Joss Bland-Hawthorn, Malgorzata Siudek, Trystan S. Lambert, Chris Power. 2025-09-16. Deep Extragalactic VIsible Legacy Survey (DEVILS): Galaxy group catalogue for the D10-COSMOS field with 90% spectroscopic redshift completeness. https://arxiv.org/abs/2509.13530

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