摘要：

From deep ROSAT PSPC and HRI observations of M86 (NGC 4406) we have mapped metal abundance and temperature changes across the image and detected significant structure in addition to the X-ray plume. We measure a high abundance in the plume of $Z \sim 0.65_{-0.2}^{+0.4}Z_\odot$, which is significantly higher than the abundance in the core of M86 (~ 0.3±0.1 Z⊙) or the cluster abundance (~0.2 Z⊙). The spectra from regions larger than the inner few arcmin show an enhanced silicon abundance. The galaxy and the plume are at similar temperatures kT ~0.8±0.03 keV, compared to the cluster temperature of ~1.9 keV. The structures detected and the abundance measurements support the hypothesis that the Virgo ICM is ram-pressure stripping the ISM of M86 in a single blob. Dust in the stripped material, previously held within cold gas clouds, is being destroyed. The morphology and calculations of the ram pressure indicate that M86 may have a southwards velocity in the plane of the sky of ~ 500 km s–1 compared to its radial velocity of 1374 km s–1 relative to the cluster.

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