| Type |
Journal Article |
| Names |
E. Iodice, M. Arnaboldi, R. P. Saglia, L. S. Sparke, O. Gerhard, J. S. Gallagher, F. Combes, F. Bournaud, M. Capaccioli, K. C. Freeman |
| Publication |
The Astrophysical Journal |
| Volume |
643 |
| Issue |
1 |
| Pages |
200-209 |
| Date |
May 1, 2006 |
| URL |
http://adsabs.harvard.edu/abs/2006ApJ...643..200I |
| Library Catalog |
NASA ADS |
| Abstract |
We have obtained high angular resolution, high signal-to-noise ratio
spectra of the calcium triplet absorption lines on the photometric axes
of the stellar spheroid in the polar disk galaxy NGC 4650A. Along the
major axis, the observed rotation and velocity dispersion measurements
show the presence of a kinematically decoupled nucleus and a flat
velocity dispersion profile. The minor-axis kinematics is determined for
the first time: along this direction some rotation is measured, and the
velocity dispersion is nearly constant and slightly increases at larger
distances from the center. The new high-resolution kinematic data
suggest that the stellar component in NGC 4650A resembles a nearly
exponential oblate spheroid supported by rotation. The main implications
of these results on the previous mass models for NGC 4650A are
discussed. Moreover, the new kinematic data set constraints on current
models for the formation scenarios of polar ring galaxies, supporting a
slow accretion rather than a secondary strong dissipative event.
Based on data collected with the FORS2 spectrograph, mounted at the UT4
of the Very Large Telescope at Cerro Paranal, Chile, operated by ESO,
during observing run 70.B-0277. |
| Tags |
Galaxies: Individual: NGC Number: NGC 4650A, galaxies: kinematics and dynamics |