The Rotation of the halo of NGC 6822 from the radial velocities of
  carbon stars
  Using spectra taken with the AAOmega spectrograph, we measure the radial
velocities of over 100 stars, many of which are intermediate age carbon stars,
in the direction of the dwarf irregular galaxy NGC 6822. Kinematic analysis
suggests that the carbon stars in the sample are associated with NGC 6822, and
estimates of its radial velocity and galactic rotation are made from a
star-by-star analysis of its carbon star population. We calculate a
heliocentric radial velocity for NGC 6822 of $-51\pm3$ \kms\ and show that the
population rotates with a mean rotation speed of $11.2\pm2.1$ \kms\ at a mean
distance of 1.1 kpc from the galactic centre, about a rotation axis with a
position angle of $26^\circ\pm13^\circ$, as projected on the sky. This is close
to the rotation axis of the HI gas disk and suggests that NGC 6822 is not a
polar ring galaxy, but is dynamically closer to a late type galaxy. However,
the rotation axis is not aligned with the minor axis of the AGB isodensity
profiles and this remains a mystery.
