English

Cluster passage driving galaxy kinematic and structural evolution in the SAMI Galaxy Survey

Astrophysics of Galaxies 2025-08-12 v1

Abstract

The cluster environment can have a significant impact on galaxy evolution. We study the impact that passage through a cluster has on stellar and ionised gas kinematics for galaxies within the Sydney-AAO Multi Integral field (SAMI) Galaxy Survey. We compute the kinematic asymmetry vasymv_{\rm asym} in the line-of-sight stellar and ionsied gas velocity maps to quantify how the cluster environment disturbs the kinematics of the stars and ionised gas. We find a significantly higher fraction of galaxies with elevated gas asymmetries in clusters compared to non-cluster environments (173+2^{+2}_{-3}\%, 26/154 vs. 111+1^{+1}_{-1}\%, 72/751), with these galaxies most likely being recent infallers passage based on their position in projected-phase-space. Compared to cluster galaxies without elevated gas asymmetries, cluster galaxies with elevated gas asymmetries have, on average, more centrally concentrated star-formation. Finally, we find the highest fraction of galaxies with elevated gas asymmetries in clusters likely to host significant substructure or be dynamically complex. Our findings are consistent with the scenario of galaxies falling into clusters, either individually or in groups, and undergoing disk-fading and a redistribution of gas, due to ram pressure stripping experienced during pericentre passage.

Keywords

Cite

@article{arxiv.2508.07589,
  title  = {Cluster passage driving galaxy kinematic and structural evolution in the SAMI Galaxy Survey},
  author = {Ryan Bagge and Caroline Foster and Sarah Brough and Oğuzhan Çakır and Luca Cortese and Franceso D'Eugenio and Scott Croom and Matt Owers and Jesse van de Sande},
  journal= {arXiv preprint arXiv:2508.07589},
  year   = {2025}
}

Comments

21 pages, 26 figures