Non-parametric Morphologies of Galaxies in the EAGLE Simulation

SUSANA PEDROSA; LUCAS BIGNONE; TISSERA, PATRICIA; TRAYFORD, J.W.

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2020 vol. 491 p. 3624 - 3642

0035-8711

We study the optical morphology of galaxies in a large-scale hydrodynamic cosmological simulation, the eagle simulation. Galaxy morphologies were characterized using non-parametric statistics (Gini, M20, Concentration and Asymmetry) derived frommock images computed using a 3D radiative transfer technique and post-processed toapproximate observational surveys. The resulting morphologies were contrasted toobservational results from a sample of log10(M∗/M) > 10 galaxies at z ∼ 0.05 in thegama survey. We find that the morphologies of eagle galaxies reproduce observations,except for asymmetry values which are larger in the simulated galaxies. Additionally,we study the effect of spatial resolution in the computation of non-parametric morphologies, finding that Gini and Asymmetry values are systematically reduced withdecreasing spatial resolution. Gini values for lower mass galaxies are especially affected.Comparing against other large scale simulations, the non-parametric statistics of eagle galaxies largely agree with those found in IllustrisTNG. Additionally, eaglegalaxies mostly reproduce observed trends between morphology and star formationrate and galaxy size. Finally, We also find a significant correlation between opticaland kinematic estimators of morphologies, although galaxy classification based onan optical or a kinematic criteria results in different galaxy subsets. The correlationbetween optical and kinematic morphologies is stronger in central galaxies than insatellites, indicating differences in morphological evolution.