Abstract
We present the stellar and ionized gas kinematics of 13 bright peculiar Virgo
cluster galaxies observed with the DensePak Integral Field Unit at the WIYN
3.5-meter telescope, to seek kinematic evidence that these galaxies have
experienced gravitational interactions or gas stripping. 2-Dimensional maps of
the stellar velocity $V$, and stellar velocity dispersion $\sigma$ and the
ionized gas velocity (H$\beta$ and/or O3) are presented for galaxies
in the sample. The stellar rotation curves and velocity dispersion profiles are
determined for 13 galaxies, and the ionized gas rotation curves are determined
for 6 galaxies. Misalignments between the optical and kinematical major axis
are found in several galaxies. While in some cases this is due to a bar, in
other cases it seems associated with a gravitational interaction or ongoing ram
pressure stripping. Non-circular gas motions are found in nine galaxies, with
various causes including bars, nuclear outflows, or gravitational disturbances.
Several galaxies have signatures of kinematically distinct stellar components,
which are likely signatures of accretion or mergers. We compute for all
galaxies the angular momentum parameter $łambda_R$. An evaluation of the
galaxies in the $łambda_R$-ellipticity plane shows that all but 2 of the
galaxies have significant support from random stellar motions, and have likely
experienced gravitational interactions. This includes some galaxies with very
small bulges and truncated/compact H$\alpha$ morphologies, indicating that such
galaxies cannot be fully explained by simple ram pressure stripping, but must
have had significant gravitational encounters. Most of the sample galaxies show
evidence for ICM-ISM stripping as well as gravitational interactions,
indicating that the evolution of a significant fraction of cluster galaxies is
likely strongly impacted by both effects.
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