Jellyfish galaxies with the IllustrisTNG simulations – I. Gas-stripping phenomena in the full cosmological context

• DOI: 10.1093/mnras/sty3156
• Publication Date: 2018-11-22T23:19:52Z
• Authors: Kiyun Yun; Annalisa Pillepich; Elad Zinger; Dylan Nelson; Martina Donnari; Gandhali Joshi; Vicente Rodriguez...; Shy Genel; Rainer Weinberger; Mark Vogelsberger; Lars Hernquist
• Keywords: Satellite galaxy

We use the IllustrisTNG simulations to study demographics and properties of jellyfish galaxies in full cosmological context. By galaxies, we mean satellites orbiting massive groups clusters that exhibit highly asymmetric distributions gas tails. In particular, select TNG100 at low redshifts (⁠|$z$| ≤ 0.6) with stellar mass exceeding |$10^{9.5} \, \mathrm{M_{\odot }}$| host halo masses range |$10^{13} \le M_{\rm 200c}/\, }}\le 10^{14.6}$|⁠. Among more than about 6000 (2600) stars (and some gas), identify 800 by visually inspecting their maps random projections. Namely, 31 per cent cluster are found signatures ram-pressure stripping gaseous tails stemming from main luminous bodies. This is a lower limit: orientation entails loss 30 an optimal projection would otherwise be identified as jellyfish. Furthermore, frequent intermediate large cluster-centric distances (r/R200c ≳ 0.25), hosts smaller satellite masses, they typically orbit supersonically. The usually extend opposite directions galaxy trajectory, no relation between tail position host's centre. Finally, late infallers (<2.5–3 Gyr ago, |$z$| = 0) emergence correlates well presence bow shocks intracluster medium.