We report results from a detailed study of the sloshing gas in the core of A496. We detect the low temperature/entropy spiral feature found in several cores, we also find that conduction between the gas in the spiral and the ambient medium must be su
ppressed by more than one order of magnitude with respect to Spitzer conductivity. Intriguingly, while the gas in the spiral features a higher metal abundance than the surrounding medium, it follows the entropy vs metal abundance relation defined by gas lying outside the spiral. The most plausible explanation for this behavior is that the low entropy metal rich plasma uplifted through the cluster atmosphere by sloshing, suffers little heating or mixing with the ambient medium. While sloshing appears to be capable of uplifting significant amounts of gas, the limited heat exchange and mixing between gas in and outside the spiral implies that this mechanism is not at all effective in: 1) permanently redistributing metals within the core region and 2) heating up the coolest and densest gas, thereby providing little or no contribution to staving of catastrophic cooling in cool cores.
We present a detailed study of the iron content of the core of the high-redshift cluster WARPJ1415.1+3612 (z=1.03). By comparing the central Fe mass excess observed in this system, M_Fe^exc = (1.67 +/- 0.40) x 10^9 M_sun, with those measured in local
cool-core systems, we infer that the bulk of the mass excess was already in place at z=1, when the age of the Universe was about half of what it is today. Our measures point to an early and intense period of star formation most likely associated with the formation of the BCG. Indeed, in the case of the power-law delay time distribution with slope -1, which reproduces the data of WARPJ1415.1+3612 best, half of the supernovae explode within 0.4 Gyr of the formation of the BCG. Finally, while for local cool-core clusters the Fe distribution is broader than the near infrared light distribution of the BCG, in WARPJ1415.1+3612 the two distributions are consistent, indicating that the process responsible for broadening the Fe distribution in local systems has not yet started in this distant cluster.
Cold-fronts in cool-core clusters are thought to be induced by minor mergers and to develop through a sloshing mechanism. While temperature and surface-brightness jumps have been detected and measured in many systems, a detailed characterization of t
he metal abundance across the discontinuity is only available for a handful of objects. Within the sloshing scenario, we expect the central cool and metal rich gas to be displaced outwards into lower abundance regions, thus generating a metal discontinuity across the front. We analyzed a long (120 ksec) XMM-Newton observation of A496 to study the metal distribution and its correlation with the cold-fronts. We find Fe discontinuities across the two main cold-fronts located ~60 kpc NNW and ~160 kpc South of the peak and a metal excess in the South direction.
