VERTICO and IllustrisTNG: The spatially resolved effects of environment on galactic gas

TL;DR

This study evaluates how well the TNG50 simulation reproduces the spatially resolved effects of cluster environments on galactic gas, finding qualitative agreement with observed gas truncation and suppression trends.

Contribution

It demonstrates that TNG50 can qualitatively replicate the spatially resolved gas effects in cluster satellite galaxies, extending previous work with TNG100.

Findings

TNG50 reproduces gas truncation in satellite galaxies.

TNG50 shows central gas density suppression similar to observations.

Simulation qualitatively matches observed gas surface density trends.

Abstract

It has been shown in previous publications that the TNG100 simulation quantitatively reproduces the observed reduction in each of the total atomic and total molecular hydrogen gas for galaxies within massive halos, i.e.~dense environments. In this Letter, we study how well TNG50 reproduces the resolved effects of a Virgo-like cluster environment on the gas surface densities of satellite galaxies with $m_* > \! 10^9\,{\rm M}_\odot$ and ${\rm SFR} \! > 0.05\,{\rm M}_\odot\,{\rm yr}^{-1}$. We select galaxies in the simulation that are analogous to those in the HERACLES and VERTICO surveys, and mock-observe them to the common specifications of the data. Although TNG50 does not quantitatively match the observed gas surface densities in the centers of galaxies, the simulation does qualitatively reproduce the trends of gas truncation and central density suppression seen in VERTICO in both HI and H$_2$. This result promises that modern cosmological hydrodynamic simulations can be used to reliably model the post-infall histories of cluster satellite galaxies.