Metal distribution in sloshing galaxy clusters: The case of A496

Abstract

We report results from a detailed study of the sloshing gas in the core of A496. We detected the low-temperature/entropy spiral feature found in several cores. We also found that conduction between the gas in the spiral and the ambient medium must be suppressed by more than one order of magnitude compared with the Spitzer conductivity. Intriguingly, while the gas in the spiral pattern features a higher metal abundance than the surrounding medium, it follows the relation of entropy vs metal abundance defined by gas outside the spiral. The most plausible explanation for this behavior is that the low-entropy metal-rich plasma that is lifted up through the cluster atmosphere by sloshing suffers little heating or mixing with the ambient medium. While sloshing appears to be capable of lifting up significant amount of gas, the limited heat exchange and mixing between gas within 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 the staving off of catastrophic cooling in cool cores.