The survival of stellar discs in Fornax-like environments, from TNG50 to real galaxies

Author(s)
Pablo M. Galán-de Anta, M. Sarzi, A. Pillepich, Y. Ding, L. Zhu, L. Coccato, E. M. Corsini, K. Fahrion, J. Falcón-Barroso, D. A. Gadotti, E. Iodice, M. Lyubenova, I. Martín-Navarro, R. M. McDermid, F. Pinna, G. van de Ven, P. T. de Zeeuw
Abstract

We study the evolution of kinematically-defined stellar discs in 10 Fornax-like clusters identified in the TNG50 run from the IllustrisTNG suite of cosmological simulations. We considered disc galaxies with present-day stellar mass $M_{\star}\geq 3 \times 10^{8} M_{\odot}$ and follow their evolution since first entering their host cluster. Very few stellar discs survive since falling in such dense environments, ranging from 40% surviving to all being disrupted. Such survival rates are consistent with what reported earlier for the two more massive, Virgo-like clusters in TNG50. In absolute terms, however, the low number of present-day disc galaxies in Fornax-like clusters could be at odds with the presence of three edge-on disc galaxies in the central regions of the actual Fornax cluster, as delineated by the Fornax3D survey. When looking at the Fornax analogues from random directions and with the same selection function of Fornax3D, the probability of finding three edge-on disc galaxies in any one Fornax-like cluster in TNG50 is rather low, albeit not impossible. We also compared the stellar-population properties near the equatorial plane derived from integral-field spectroscopy for the three edge-ons in Fornax to similar line-of-sight integrated values for present-day disc galaxies in TNG50. For one of these, the very old and metal-rich stellar population of its disc cannot be matched by any the disc galaxies in TNG50, including objects in the field. We discuss possible interpretations of these findings, while pointing to future studies on passive cluster spirals as a way to further test state-of-the-art cosmological simulations.

Organisation(s)
Department of Astrophysics
External organisation(s)
Chinese Academy of Sciences (CAS), Queen's University Belfast, Armagh Observatory and Planetarium, Max-Planck-Institut für Astronomie, University of the Chinese Academy of Sciences, European Southern Observatory (Germany), University of Padova, Osservatorio Astronomico, Science and Operations Department - Science Division (SCI-SC), Instituto de Astrofísica de Canarias, Universidad de La Laguna, INAF Astronomical Observatory of Capodimonte , Macquarie University, Leiden University
Journal
Monthly Notices of the Royal Astronomical Society
Volume
517
Pages
5992-6003
No. of pages
12
ISSN
0035-8711
DOI
https://doi.org/10.1093/mnras/stac3061
Publication date
12-2022
Peer reviewed
Yes
Austrian Fields of Science 2012
103003 Astronomy, 103004 Astrophysics
Keywords
ASJC Scopus subject areas
Astronomy and Astrophysics, Space and Planetary Science
Portal url
https://ucris.univie.ac.at/portal/en/publications/the-survival-of-stellar-discs-in-fornaxlike-environments-from-tng50-to-real-galaxies(234998e6-6b59-437d-afae-0567655bfedd).html