The evolution of galaxy cluster X-ray scaling relations

Short, C J, Thomas, P A, Young, O E, Pearce, F R, Jenkins, A and Muanwong, O (2010) The evolution of galaxy cluster X-ray scaling relations. Monthly Notices of the Royal Astronomical Society, 408 (4). pp. 2213-2233. ISSN 0035-8711

PDF (The definitive version is available at - Published Version
Download (1MB) | Preview


We use numerical simulations to investigate, for the first time, the joint effect of feedback from supernovae (SNe) and active galactic nuclei (AGN) on the evolution of galaxy cluster X-ray scaling relations. Our simulations are drawn from the Millennium Gas Project and are some of the largest hydrodynamical N-body simulations ever carried out. Feedback is implemented using a hybrid scheme, where the energy input into intracluster gas by SNe and AGN is taken from a semi-analytic model of galaxy formation. This ensures that the source of feedback is a population of galaxies that closely resembles that found in the real Universe. We show that our feedback model is capable of reproducing observed local X-ray scaling laws, at least for non-cool-core clusters, but that almost identical results can be obtained with a simplistic preheating model. However, we demonstrate that the two models predict opposing evolutionary behaviour. We have examined whether the evolution predicted by our feedback model is compatible with observations of high-redshift clusters. Broadly speaking, we find that the data seem to favour the feedback model for z <~ 0.5, and the preheating model at higher redshift. However, a statistically meaningful comparison with observations is impossible, because the large samples of high-redshift clusters currently available are prone to strong selection biases. As the observational picture becomes clearer in the near future, it should be possible to place tight constraints on the evolution of the scaling laws, providing us with an invaluable probe of the physical processes operating in galaxy clusters.

Item Type: Article
Keywords: Hydrodynamics - methods, Numerical - galaxies, Clusters - general, Galaxies - clusters, Intracluster medium, X-rays - galaxies, Clusters
Schools and Departments: School of Mathematical and Physical Sciences > Physics and Astronomy
Subjects: Q Science > QB Astronomy
Depositing User: Peter Thomas
Date Deposited: 01 Nov 2012 10:15
Last Modified: 07 Aug 2019 09:17

View download statistics for this item

📧 Request an update