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arXiv · 2003.07476

SuperModel Predictions in the Outskirts of the Galaxy Cluster Zwicky 3146

Roberto Fusco-Femiano
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Abstract

The relaxed galaxy cluster Zwicky 3146 is analyzed via the SuperModel, a tool already tested on many clusters since 2009. In particular, this analysis is focused on the intracluster medium X-ray temperature data measured by XMM-Newton up to r_{500}. A previous analysis was based on the temperature profile derived from the Sunyaev-Zeldovich effect pressure data. The gas mass fraction f_{gas} is obtained from the resulting SuperModel temperature profile extrapolated up to the virial radius R, that turns out in agreement with the steep temperature profiles observed by Suzaku, and from the gas density profile observed by XMM-Newton. The comparison between f_{gas} with the universal value indicates a non-thermal pressure component, p_{nth}, in the cluster outskirts. The SuperModel analysis shows a ratio alpha(R) (about 50%) of p_{nth} to the total pressure greater than the values found by simulations, highlighting the possible presence of accreting substructures and inhomogeneities in the gas density profile. Once that this profile is corrected for clumpiness, the level of p_{nth} is considerably reduced. However, a significant turbulence (alpha(R) about 20%) and entropy flattening are still present in the outskirts of the galaxy cluster Zwicky 3146.

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Roberto Fusco-Femiano. 2020-03-16. SuperModel Predictions in the Outskirts of the Galaxy Cluster Zwicky 3146. https://doi.org/10.1093/mnras/staa759

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