Probing turbulence in the Coma galaxy cluster
Finoguenov, A.; Böhringer, H.; Miniati, F.; Briel, U. G.; Schuecker, P.
Germany
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 ∼ 10 percent of the total intracluster medium pressure in turbulent form. The results also provide observational constraints on the viscosity of the gas.
Based on observations with XMM-Newton, an ESA Science Mission with instruments and contributions directly funded by ESA Member States and the USA (NASA).