Metal transport by gas sloshing in M87
  We present the results of an XMM-Newton mosaic covering the central ~200 kpc
of the nearby Virgo cluster. We focus on a strong surface brightness
discontinuity in the outskirts of the brightest cluster galaxy, M87. Using both
XMM-Newton and Suzaku, we derive accurate temperature and metallicity profiles
across this feature and show that it is a cold front probably due to sloshing
of the Virgo ICM. It is also associated with a discontinuity in the chemical
composition. The gas in the inner, bright region of the front is ~40% more
abundant in Fe than the gas outside the front, suggesting the important role of
sloshing in transporting metals through the ICM. For the first time, we provide
a quantitative estimate of the mass of Fe transported by a cold front. This
amounts to ~6% of the total Fe mass within the radial range affected by
sloshing, significantly more than the amount of metals transported by the AGN
in the same cluster core. The very low Fe abundance of only ~0.2 solar
immediately outside the cold front at a radius of 90 kpc suggests we are
witnessing first-hand the transport of higher metallicity gas into a pristine
region, whose abundance is typical of the cluster outskirts. The Mg/Fe and O/Fe
abundance ratios remain approximately constant over the entire radial range
between the centre of M87 and the faint side of the cold front, which requires
the presence of a centrally peaked distribution not only for Fe but also for
core-collapse type supernova products. This peak may stem from the star
formation triggered as the BCG assembled during the protocluster phase.
