Ram pressure stripping of the multiphase ISM and star formation in the
  Virgo spiral galaxy NGC 4330
  It has been shown that the Virgo spiral galaxy NGC 4330 shows signs of
ongoing ram pressure stripping in multiple wavelengths: at the leading edge of
the interaction, the Halpha and dust extinction curve sharply out of the disk;
on the trailing side, a long Halpha/UV tail has been found which is located
upwind of a long HI tail. We complete the multiwavelength study with IRAM 30m
HERA CO(2-1) and VLA 6 cm radio continuum observations of NGC 4330. The data
are interpreted with the help of a dynamical model including ram pressure and,
for the first time, star formation. Our best-fit model reproduces qualitatively
the observed projected position, radial velocity of the galaxy, the molecular
and atomic gas distribution and velocity field, and the UV distribution in the
region where a gas tail is present. However, the observed red UV color on the
windward side is currently not reproduced by the model. Based on our model, the
galaxy moves to the north and still approaches the cluster center with the
closest approach occurring in ~100 Myr. In contrast to other Virgo spiral
galaxies affected by ram pressure stripping, NGC 4330 does not show an
asymmetric ridge of polarized radio continuum emission. We suggest that this is
due to the relatively slow compression of the ISM and the particular projection
of NGC 4330. The observed offset between the HI and UV tails is well reproduced
by our model. Since collapsing and starforming gas clouds decouple from the ram
pressure wind, the UV-emitting young stars have the angular momentum of the gas
at the time of their creation. On the other hand, the gas is constantly pushed
by ram pressure. The reaction (phase change, star formation) of the multiphase
ISM (molecular, atomic, ionized) to ram pressure is discussed in the framework
of our dynamical model.
