Skip to main content

Research Repository

Advanced Search

The EAGLE simulations of galaxy formation: calibration of subgrid physics and model variations

Crain, R.A.; Schaye, J.; Bower, R.G.; Furlong, M.; Schaller, M.; Theuns, T.; Dalla Vecchia, C.; Frenk, C.S.; McCarthy, I.G.; Helly, J.C.; Jenkins, A.; Rosas-Guevara, Y.M.; White, S.D.M.; Trayford, J.W.

The EAGLE simulations of galaxy formation: calibration of subgrid physics and model variations Thumbnail


R.A. Crain

J. Schaye

R.G. Bower

M. Furlong

M. Schaller

C. Dalla Vecchia

I.G. McCarthy

J.C. Helly

Y.M. Rosas-Guevara

S.D.M. White

J.W. Trayford


We present results from 13 cosmological simulations that explore the parameter space of the ‘Evolution and Assembly of GaLaxies and their Environments’ (EAGLE) simulation project. Four of the simulations follow the evolution of a periodic cube L = 50 cMpc on a side, and each employs a different subgrid model of the energetic feedback associated with star formation. The relevant parameters were adjusted so that the simulations each reproduce the observed galaxy stellar mass function at z = 0.1. Three of the simulations fail to form disc galaxies as extended as observed, and we show analytically that this is a consequence of numerical radiative losses that reduce the efficiency of stellar feedback in high-density gas. Such losses are greatly reduced in the fourth simulation – the EAGLE reference model – by injecting more energy in higher density gas. This model produces galaxies with the observed size distribution, and also reproduces many galaxy scaling relations. In the remaining nine simulations, a single parameter or process of the reference model was varied at a time. We find that the properties of galaxies with stellar mass ≲ M⋆ (the ‘knee’ of the galaxy stellar mass function) are largely governed by feedback associated with star formation, while those of more massive galaxies are also controlled by feedback from accretion on to their central black holes. Both processes must be efficient in order to reproduce the observed galaxy population. In general, simulations that have been calibrated to reproduce the low-redshift galaxy stellar mass function will still not form realistic galaxies, but the additional requirement that galaxy sizes be acceptable leads to agreement with a large range of observables.


Crain, R., Schaye, J., Bower, R., Furlong, M., Schaller, M., Theuns, T., …Trayford, J. (2015). The EAGLE simulations of galaxy formation: calibration of subgrid physics and model variations. Monthly Notices of the Royal Astronomical Society, 450(2), 1937-1961.

Journal Article Type Article
Acceptance Date Mar 30, 2015
Online Publication Date Apr 29, 2015
Publication Date Jun 21, 2015
Deposit Date Feb 10, 2016
Publicly Available Date Feb 16, 2016
Journal Monthly Notices of the Royal Astronomical Society
Print ISSN 0035-8711
Electronic ISSN 1365-2966
Publisher Royal Astronomical Society
Peer Reviewed Peer Reviewed
Volume 450
Issue 2
Pages 1937-1961
Keywords Galaxies: evolution, Galaxies: formation, Galaxies: haloes, Cosmology: theory.


Published Journal Article (1.6 Mb)

Copyright Statement
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.

You might also like

Downloadable Citations