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We present in this paper a substructure and spectroimaging study of the Coma cluster of galaxies based on XMM-Newton data. XMM-Newton performed a mosaic of observations of Coma to ensure a large coverage of the cluster. We add the different pointings together and fit elliptical beta-models to the data. We subtract the cluster models from the data and look for residuals, which can be interpreted as substructure. We find several significant structures: the well-known subgroup connected to NGC4839 in the South-West of the cluster, and another substructure located between NGC 4839 and the centre of the Coma cluster. Constructing a hardness ratio image, which can be used as a temperature map we see that in front of this new structure the temperature is significantly increased (higher or equal 10 keV). We interpret this temperature enhancement as the result of heating as this structure falls onto the Coma cluster. We furthermore reconfirm the filament-like structure South-East of the cluster centre. This region is significantly cooler than the mean cluster temperature. We estimate the temperature of this structure to be equal or below 1keV. A possible scenario to explain the observed features is stripping caused by the infall of a small group of galaxies located around the two galaxies NGC4921 and NGC4911 into the Coma cluster with a non-zero impact parameter. We also see significant X-ray depressions North and South-East of NGC4921, which might either be linked to tidal forces due to the merger with the Western structure or connected to an older cluster merger.
Using XMM Newton data, we investigate the nature of the X-ray emission in the radio relic 1253+275 in the Coma cluster. We determine the conditions of the cluster gas to check current models of relic formation, and we set constraints on the intraclus
We present here the first analysis of the XMM Newton EPIC-MOS data of the galaxy group around NGC4839, which lies at a projected distance to the Coma cluster center of 1.6Mpc. In our analysis, which includes imaging, spectro-imaging and spectroscopy
We present a temperature map and a temperature profile of the central part (r < 20 or 1/4 virial radius) of the Coma cluster. We combined 5 overlapping pointings made with XMM/EPIC/MOS and extracted spectra in boxes of 3.5 X 3.5. The temperature dist
The Narrow Line Seyfert 1 galaxy NGC4051 shows unusual low flux states, lasting several months, when the 2-10 keV X-ray spectrum becomes unusually hard (photon index<1) while the spectrum at lower X-ray energies is dominated by a large soft excess. A
The quantity Y_ X, the product of the X-ray temperature T_ X and gas mass M_ g, has recently been proposed as a robust low-scatter mass indicator for galaxy clusters. Using precise measurements from XMM-Newton data of a sample of 10 relaxed nearby cl