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arXiv · 1510.04270

Chandra Measurements of a Complete Sample of X-ray Luminous Galaxy Clusters: The Luminosity-Mass Relation

P. A. Giles·B. J. Maughan·H. Dahle·M. Bonamente·D. Landry·C. Jones·M. Joy·S. S. Murray·N. van der Pyl
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Abstract

We present the results of work involving a statistically complete sample of 34 galaxy clusters, in the redshift range 0.15$\le$z$\le$0.3 observed with $Chandra$. We investigate the luminosity-mass ($LM$) relation for the cluster sample, with the masses obtained via a full hydrostatic mass analysis. We utilise a method to fully account for selection biases when modeling the $LM$ relation, and find that the $LM$ relation is significantly different than the relation modelled when not account for selection effects. We find that the luminosity of our clusters is 2.2$\pm$0.4 times higher (when accounting for selection effects) than the average for a given mass, its mass is 30% lower than the population average for a given luminosity. Equivalently, using the $LM$ relation measured from this sample without correcting for selection biases would lead to the underestimation by 40% of the average mass of a cluster with a given luminosity. Comparing the hydrostatic masses to mass estimates determined from the $Y_{X}$ parameter, we find that they are entirely consistent, irrespective of the dynamical state of the cluster.

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P. A. Giles, B. J. Maughan, H. Dahle, M. Bonamente, D. Landry, C. Jones, M. Joy, S. S. Murray, N. van der Pyl. 2016-10-14. Chandra Measurements of a Complete Sample of X-ray Luminous Galaxy Clusters: The Luminosity-Mass Relation. https://doi.org/10.1093/mnras%2Fstw2621

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