The physics of the coolest phases in the hot Intra-Cluster Medium (ICM) ofclusters of galaxies is yet to be fully unveiled. X-ray cavities blown by thecentral Active Galactic Nucleus (AGN) contain enough energy to heat thesurrounding gas and stop cooling, but locally blobs or filaments of gas appearto be able to cool to low temperatures of 10^4 K. In X-rays, however, gas withtemperatures lower than 0.5 keV is not observed. Using a deep XMM-Newtonobservation of the cluster of galaxies Abell 2052, we derive 2D maps of thetemperature, entropy, and iron abundance in the core region. About 130 kpcSouth-West of the central galaxy, we discover a discontinuity in the surfacebrightness of the hot gas which is consistent with a cold front. Interestingly,the iron abundance jumps from ~0.75 to ~0.5 across the front. In a smallerregion to the North-West of the central galaxy we find a relatively highcontribution of cool 0.5 keV gas, but no X-ray emitting gas is detected belowthat temperature. However, the region appears to be associated with much coolerH-alpha filaments in the optical waveband. The elliptical shape of the coldfront in the SW of the cluster suggests that the front is caused by sloshing ofthe hot gas in the clusters gravitational potential. This effect is probably animportant mechanism to transport metals from the core region to the outer partsof the cluster. The smooth temperature profile across the sharp jump in themetalicity indicates the presence of heat conduction and the lack of mixingacross the discontinuity. The cool blob of gas NW of the central galaxy wasprobably pushed away from the core and squeezed by the adjacent bubble, whereit can cool efficiently and relatively undisturbed by the AGN. Shock inducedmixing between the two phases may cause the 0.5 keV gas to cool non-radiativelyand explain our non-detection of gas below 0.5 keV.
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