The optical morphologies of galaxies in the IllustrisTNG simulation: a comparison to Pan-STARRS observations
Name
1809.08239.pdf
Description
Accepted version
Size
2.02 MB
Format
Adobe PDF
Checksum (MD5)
611036769042c7c166f0b7e5fa649d6a
Author(s)
Rodriguez-Gomez, Vicente
Snyder, Gregory F
Lotz, Jennifer M
Nelson, Dylan
Pillepich, Annalisa
Springel, Volker
Genel, Shy
Weinberger, Rainer
Tacchella, Sandro
Pakmor, Rüdiger
Date Issued
2019
Journal
Monthly Notices of the Royal Astronomical Society
Publisher
Oxford University Press (OUP)
Version
Author's final manuscript
Abstract
© 2018 The Author(s). We have generated synthetic images of ∼27 000 galaxies from the IllustrisTNG and the original Illustris hydrodynamic cosmological simulations, designed to match Pan-STARRS observations of log10(M∗/M·)-∼9.8-11.3 galaxies at z ∼0.05. Most of our synthetic images were created with the SKIRT radiative transfer code, including the effects of dust attenuation and scattering, and performing the radiative transfer directly on the Voronoi mesh used by the simulations themselves. We have analysed both our synthetic and real Pan-STARRS images with the newly developed statmorph code, which calculates non-parametric morphological diagnostics-including the Gini-M20 and concentration-asymmetry-smoothness statistics-and performs 2D Sersic fits. Overall, we find that the optical morphologies of IllustrisTNG galaxies are in good agreement with observations, and represent a substantial improvement compared to the original Illustris simulation. In particular, the locus of the Gini-M20 diagram is consistent with that inferred from observations, while the median trends with stellar mass of all the morphological, size and shape parameters considered in this work lie within the ∼1s scatter of the observational trends. However, the IllustrisTNG model has some difficulty with more stringent tests, such as producing a strong morphology-colour relation. This results in a somewhat higher fraction of red discs and blue spheroids compared to observations. Similarly, the morphology-size relation is problematic: while observations show that discs tend to be larger than spheroids at a fixed stellar mass, such a trend is not present in IllustrisTNG.
MIT Department
Massachusetts Institute of Technology. Department of Physics
MIT Kavli Institute for Astrophysics and Space Research
Terms of Use
Creative Commons Attribution-Noncommercial-Share Alike
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1093/MNRAS/STY3345
