The impact of disturbed galaxy clusters on the kinematics of active galactic nuclei

Bilton, Lawrence E.; Pimbblet, Kevin A.; Gordon, Yjan A.

Abstract

© 2020 The Author(s) We produce a kinematic analysis of AGN-hosting cluster galaxies from a sample of 33 galaxy clusters selected using the X-ray Clusters Database (BAX) and populated with galaxies from the Sloan Digital Sky Survey Data Release 8. The 33 galaxy clusters are delimited by their relative intensity of member galaxy substructuring as a proxy to core merging to derive two smaller sub-samples of 8 dynamically active (merging) and 25 dynamically relaxed (non-merging) states. The AGN were selected for each cluster sub-sample by employing the WHAN diagram to the strict criteria of log10([N II]/Hα) ≥ −0.32 and EWHα ≥ 6 Å, providing pools of 70 mergings and 225 non-merging AGN sub-populations. By co-adding the clusters to their respective dynamical states to improve the signal-to-noise ratio of our AGN sub-populations we find that merging galaxy clusters on average host kinematically active AGN between 0-1.5r200 as r200 → 0, where their velocity dispersion profile (VDP) presents a significant deviation from the non-AGN sub-population VDP by ≳3σ. This result is indicative that the AGN-hosting cluster galaxies have recently coalesced on to a common potential. Further analysis of the composite distributions illustrates non-merging AGN-hosting sub-populations have, on average, already been accreted and predominantly lie within backsplash regions of the projected phase-space. This suggests merging cluster dynamical states hold relatively younger AGN sub-populations kinematically compared with those found in non-merging cluster dynamical states.

Citation

Bilton, L. E., Pimbblet, K. A., & Gordon, Y. A. (2020). The impact of disturbed galaxy clusters on the kinematics of active galactic nuclei. Monthly notices of the Royal Astronomical Society, 499(3), 3792-3805. https://doi.org/10.1093/mnras/staa3154

• Journal Article Type: Article
• Acceptance Date: Oct 8, 2020
• Online Publication Date: Oct 14, 2020
• Publication Date: 2020-12
• Deposit Date: Dec 17, 2020
• Publicly Available Date: Dec 18, 2020
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Electronic ISSN: 1365-2966
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 499
• Issue: 3
• Pages: 3792-3805
• DOI: https://doi.org/10.1093/mnras/staa3154
• Keywords: Galaxies - active; Galaxies - clusters - general; Galaxies - kinematics and dynamics
• Public URL: https://hull-repository.worktribe.com/output/3673983
• Publisher URL: https://academic.oup.com/mnras/article-abstract/499/3/3792/5923574?redirectedFrom=fulltext