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arXiv · 1803.02373

The SLUGGS Survey: A comparison of total-mass profiles of early-type galaxies from observations and cosmological simulations, to $\sim$4 effective radii

Sabine Bellstedt·Duncan A. Forbes·Aaron J. Romanowsky·Rhea-Silvia Remus·Adam R. H. Stevens·Jean P. Brodie·Adriano Poci·Richard McDermid·Adebusola Alabi·Leonie Chevalier·Caitlin Adams·Anna Ferré-Mateu·Asher Wasserman·Viraj Pandya
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Abstract

We apply the Jeans Anisotropic MGE (JAM) dynamical modelling method to SAGES Legacy Unifying Globulars and GalaxieS (SLUGGS) survey data of early-type galaxies in the stellar mass range $10^{10} 10^{10.7}{\rm M}_{\odot}$ in the Magneticum simulations, we identify a significant anticorrelation between total-mass density profile slopes and the fraction of stellar mass formed ex situ (i.e. accreted), whereas this anticorrelation is weaker for lower stellar masses, implying that the measured total mass density slopes for low-mass galaxies are less likely to be determined by merger activity.

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Sabine Bellstedt, Duncan A. Forbes, Aaron J. Romanowsky, Rhea-Silvia Remus, Adam R. H. Stevens, Jean P. Brodie, Adriano Poci, Richard McDermid, Adebusola Alabi, Leonie Chevalier, Caitlin Adams, Anna Ferré-Mateu, Asher Wasserman, Viraj Pandya. 2018-05-25. The SLUGGS Survey: A comparison of total-mass profiles of early-type galaxies from observations and cosmological simulations, to $\sim$4 effective radii. https://doi.org/10.1093/mnras%2Fsty456

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