Active galactic nuclei in diverse galactic environments




Patel, Divya; Robertson, Clayton; Holwerda, Benne; Pimbblet, Kevin; Kirkpatrick, Allison; De Propris, Roberto; Liske, Jochen

PublisherCambridge University Press (CUP)

2026

 Publications of the Astronomical Society of Australia

e020

43

1323-3580

1448-6083

DOIhttps://doi.org/10.1017/pasa.2026.10153

https://doi.org/10.1017/pasa.2026.10153

https://research.utu.fi/converis/portal/detail/Publication/515886020



We examine how the presence of active galactic nuclei (AGN) correlates with location in large-scale cosmic structures using the Galaxy and Mass Assembly (GAMA) survey across the G09, G12, and G15 fields. Our sample contains 18 927, 9 273, and 1 148 galaxies for highly dense filaments, moderately dense tendrils, and highly underdense voids, respectively. AGN are identified among emission-line galaxies using Baldwin-Phillips-Terlevich (BPT) diagnostic diagrams based on [NII], [SII], and [OI]. We compare AGN fractions across filament, tendril, and void regions and as a function of distance from the nearest filament centreline. Our results reveal a mild excess in filaments compared to voids when using [SII]- and [NII]-based classifications, while no significant environmental dependence is found for [OI]-based classifications. Overall, we find a weak environmental trend with AGN activity, which suggests that the local environment does not always dominate AGN activity; instead, secular processes are likely to be at play. Our findings are consistent with previous studies reporting only marginal preferences for overdense environments for AGN.


We acknowledge the support of the Summer Research Opportunity Program (SROP), the Jones Scholars Program, and the Undergraduate Research Grant (URG) by the University of Louisville's Office of the Executive Vice President for Research and Innovation (EVPRI).


Last updated on 20/03/2026 07:36:59 AM