Planetary nebula kinematics in NGC 1316: a young Sombrero
  Aims. We present positions and velocities for 796 planetary nebulae (PNe) in
the Fornax Brightest Cluster Galaxy NGC 1316 (Fornax A). The planetary nebulae
and existing kinematics are used to explore the rotation of this merger remnant
and constrain dynamical models. Methods. Using FORS2 on the VLT, the PN
velocities were measured using a counter-dispersed slitless-spectroscopy
technique that produced the largest-to-date sample outside of the Local Group.
Spherical, non-rotating, constant-anisotropy Jeans models were con- strained by
observations of the planetary nebulae and existing integrated light spectra.
Results. The two-dimensional velocity field indicates dynamically-important
rotation that rises in the outer parts, possibly due to the outward transfer of
angular momentum during the merger. The modeling indicates a high dark matter
content, particularly in the outer parts, that is consistent with previous
estimates from dynamical models, lensing and stellar population models.
Conclusions. The exceptionally large sample of PN velocities makes it possible
to explore the kinematics of NGC 1316 in detail. Comparing the results to other
early-type galaxies like NGC 1399 and NGC 4594 (M104, Sombrero), NGC 1316
represents a transi- tion phase from a major-merger event to a bulge-dominated
galaxy like NGC 4594.
