Abstract
The detailed comparison between observations and simulations of ram pressure
stripped spiral galaxies in the Virgo cluster has led to a three dimensional
view of the galaxy orbits within the hot intracluster medium. The 3D velocities
and Mach numbers derived from simulations can be used to derive simple Mach
cone geometries for Virgo spiral galaxies. We search for indications of hot gas
within Mach cones in X-ray observations of selected Virgo Cluster spiral
galaxies (NGC 4569, NGC 4388, and NGC 4501). We find extraplanar diffuse X-ray
emission in all galaxies. Based on the 3D velocity vectors from dynamical
modelling a simple Mach cone is fitted to the triangular shape of NGC 4569's
diffuse X-ray emission. Assuming that all extraplanar diffuse X-ray emission
has to be located inside the Mach cone, we also fit Mach cones to NGC 4388's
and NGC 4501's extraplanar X-ray emission. For NGC 4569 it is hard to reconcile
the derived Mach cone opening angle with a Mach number based on the sound speed
alone. Instead, a Mach number involving the Alfvénic speed seems to be more
appropriate, yielding a magnetic field strength of $3$-6 $\mu$G for a
intracluster medium density of $n 10^-4$ cm$^-3$. Whereas the
temperature of the hot component of NGC 4569's X-ray halo (0.5 keV) is at the
high end but typical for a galactic outflow, the temperature of the hot gas
tails of NGC 4388 and NGC 4501 are significantly hotter (0.7-0.9 keV). In NGC
4569 we find direct evidence for a Mach cone which is filled with hot gas from
a galactic superwind. We suggest that the high gas temperatures in the X-ray
tails of NGC 4388 and NGC 4501 are due to the mixing of the stripped ISM into
the hot intracluster medium of the Virgo cluster.
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