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XMM-Newton Observations of Evolution of Cluster X-Ray Scaling Relations at z=0.4-0.7

O. Kotov·A. Vikhlinin
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Abstract

We present a spatially-resolved analysis of the temperature and gas density profiles of galaxy clusters at z=0.4-0.7 observed with XMM-Newton. These data are used to derive the total cluster mass within the radius r_500 without assuming isothermality, and also to measure the average temperature and total X-ray luminosity excluding the cooling cores. We derive the high-redshift M-T and L-T relations and compare them with the local measurements. The high-redshift L-T relation has low scatter and evolves as L ~ (1+z)^{1.8\pm0.3} for a fixed T, in good agreement with several previous Chandra and XMM-Newton studies (Vikhlinin et al., Lumb et al., Maughan et al.). The observed evolution of the M-T relation follows M_500 = A T^{3/2} E(z)^{-alpha}, where we measure alpha=0.88\pm0.23. This is in good agreement with predictions of the self-similar theory, alpha=1.

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O. Kotov, A. Vikhlinin. 2005-09-22. XMM-Newton Observations of Evolution of Cluster X-Ray Scaling Relations at z=0.4-0.7. https://doi.org/10.1086/433170

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