The wobbly Galaxy: kinematics north and south with RAVE red clump giants
  The RAVE survey, combined with proper motions and distance estimates, can be
used to study in detail stellar kinematics in the extended solar neighbourhood
(solar suburb). Using the red clump, we examine the mean velocity components in
3D between an R of 6 and 10 kpc and a Z of -2 to 2 kpc, concentrating on
North-South differences. Simple parametric fits to the R, Z trends for VPHI and
the velocity dispersions are presented. We confirm the recently discovered
gradient in mean Galactocentric radial velocity, VR, finding that the gradient
is more marked below the plane, with a Z gradient also present. The vertical
velocity, VZ, also shows clear structure, with indications of a
rarefaction-compression pattern, suggestive of wave-like behaviour. We perform
a rigorous error analysis, tracing sources of both systematic and random
errors. We confirm the North-South differences in VR and VZ along the
line-of-sight, with the VR estimated independent of the proper motions. The
complex three-dimensional structure of velocity space presents challenges for
future modelling of the Galactic disk, with the Galactic bar, spiral arms and
excitation of wave-like structures all probably playing a role.
