Schaller, M and Frenk, CS and Bower, RG and Theuns, T and Jenkins, A and Schaye, J and Crain, RA and Furlong, M and Vecchia, CD and McCarthy, IG (2015) Baryon effects on the internal structure of LCDM halos in the EAGLE simulations. Monthly Notices of the Royal Astronomical Society, 451 (2). pp. 1247-1267. ISSN 0035-8711

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Abstract

We investigate the internal structure and density profiles of halos of mass $10^{10}-10^{14}~M_\odot$ in the Evolution and Assembly of Galaxies and their Environment (EAGLE) simulations. These follow the formation of galaxies in a $\Lambda$CDM Universe and include a treatment of the baryon physics thought to be relevant. The EAGLE simulations reproduce the observed present-day galaxy stellar mass function, as well as many other properties of the galaxy population as a function of time. We find significant differences between the masses of halos in the EAGLE simulations and in simulations that follow only the dark matter component. Nevertheless, halos are well described by the Navarro-Frenk-White (NFW) density profile at radii larger than ~5% of the virial radius but, closer to the centre, the presence of stars can produce cuspier profiles. Central enhancements in the total mass profile are most important in halos of mass $10^{12}-10^{13}M_\odot$, where the stellar fraction peaks. Over the radial range where they are well resolved, the resulting galaxy rotation curves are in very good agreement with observational data for galaxies with stellar mass $M_*<5\times10^{10}M_\odot$. We present an empirical fitting function that describes the total mass profiles and show that its parameters are strongly correlated with halo mass.

Item Type:	Article
Additional Information:	This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2015 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved
Uncontrolled Keywords:	0201 Astronomical And Space Sciences
Subjects:	Q Science > QB Astronomy
Divisions:	Astrophysics Research Institute
Publisher:	Oxford University Press
Related URLs:	Author
Date Deposited:	28 Oct 2015 14:01
Last Modified:	28 Oct 2015 14:01
DOI or Identification number:	10.1093/mnras/stv1067
URI:	http://researchonline.ljmu.ac.uk/id/eprint/369

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• The masses and density profiles of halos in a LCDM galaxy formation simulation. (deposited 07 Jan 2015 15:17)
  • Baryon effects on the internal structure of LCDM halos in the EAGLE simulations. (deposited 28 Oct 2015 14:01) [Currently Displayed]

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