Work

Environmental dependence of galaxy properties in the DESI DR1 Bright Galaxy Survey: Star formation, morphology, and AGN activity at z < 0.55

Year: 2026

Type: article

Abstract: We examined the environmental dependence of galaxy properties using a parent sample of about 1.4 million BGS_BRIGHT galaxies from the Dark Energy Spectroscopic Instrument Data Release 1 Bright Galaxy Survey at 0.05 < z < 0.55. Using the extended halo-based group catalogue, we measured how the specific star formation rate (sSFR), Sérsic index, and active galactic nucleus fraction depend on halo mass over 9 ≤ log( M * /M ⊙ ) < 12 and 12.5 ≤ log( M h /M ⊙ ) < 16. The parent measurements describe the observed sample, and our main conclusions about the galaxy population are based on comparisons above the completeness limit derived for quiescent galaxies. Within the same stellar mass and redshift bins, the median sSFR is generally lower in clusters than in the field. At intermediate stellar masses and z < 0.25, satellites show a lower median sSFR than centrals at fixed stellar and halo mass. The environmental dependence of the star formation reflects differences between centrals and satellites and the changing satellite fraction. The Sérsic index increases only weakly with halo mass at fixed stellar mass and redshift. Among galaxies in which all four diagnostic emission lines are detected, we find no strong environmental dependence of Seyfert or low-ionisation nuclear emission-line region fractions at fixed stellar mass. They are both marginally higher at most in clusters, with the largest but most uncertain differences at the highest stellar masses.

Source: Astronomy and Astrophysics

DOI: 10.1051/0004-6361/202660182

Author: D. Kim

Institution: Chungnam National University

Language: English

Topic: Galaxies: Formation, Evolution, Phenomena

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $1,865