Challenging the merger-sloshing cold front paradigm with an observation of A2142

A2142 is the first cluster in which cold fronts were observed. Two strikingsurface brightness discontinuities are visible even to an untrained eye inChandra images and the pressure profiles are almost continuous across them,providing textbook examples of cold fronts. However, A2142 does not fit withinthe now dominant scenario, that describes cold fronts either as the edges ofmerging subclusters or as the cool cores sloshing.. in the potential well oftheir host cluster. This ambiguity may be due to an incomplete picture of thedynamical state of A2142 or alternatively to the inadequacy of the currentscenario of cold front formation. We propose a 50 ks XMMNewton observation tocharacterize the dynamical state of A2142 well enough to resolve this issue. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]