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Probing Turbulence in the Coma Galaxy Cluster

P. Schuecker·A. Finoguenov·F. Miniati·H. Boehringer·U. G. Briel
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Abstract

Spatially-resolved gas pressure maps of the Coma galaxy cluster are obtained from a mosaic of XMM-Newton observations in the scale range between a resolution of 20 kpc and an extent of 2.8 Mpc. A Fourier analysis of the data reveals the presence of a scale-invariant pressure fluctuation spectrum in the range between 40 and 90 kpc and is found to be well described by a projected Kolmogorov/Oboukhov-type turbulence spectrum. Deprojection and integration of the spectrum yields the lower limit of $\sim 10$ percent of the total intracluster medium pressure in turbulent form. The results also provide observational constraints on the viscosity of the gas.

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P. Schuecker, A. Finoguenov, F. Miniati, H. Boehringer, U. G. Briel. 2004-07-26. Probing Turbulence in the Coma Galaxy Cluster. https://doi.org/10.1051/0004-6361%3A20041039

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