Interacting binary galaxies. 7: Kinematic data for 12 disturbed ellipticals

Borne, Kirk D.; Balcells, Marc; Hoessel, John G.; McMaster, Matthew
Bibliographical reference

Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 435, no. 1, p. 79-92

Advertised on:
11
1994
Number of authors
4
IAC number of authors
0
Citations
14
Refereed citations
14
Description
We have analyzed long-slit spectroscopic data for a sample of 12 tidally disturbed elliptical galaxies. The spectra were obtained with the Kitt Peak National Observatory (KPNO) 4 m RC spectrograph. Rotation curves and velocity dispersion profiles have been measured at a variety of position angles in these galaxies and have been used to analyze the dynamical response and internal kinematics of stellar systems involved in strong gravitational encounters. We have confirmed with these data our previous observation that such galaxies often reveal U-shaped 'rotation' profiles, indicative of a strong resonant tidal effect among those stars that are moving prograde with respect to the galactic encounter. Additional kinematic peculiarities, including U-shaped and W-shaped velocity dispersion profiles, are also revealed in these data. The observed morphologies of the tidal features seen in some of the sample galaxies are consistent with the idea that elliptical galaxies often contain an embedded disk component. Our velocity profiles along new position angles confirm the validity of tidal interaction models that we previously derived for specific pairs in our sample using only a single slit position angle per galaxy. Additional insight into possible refinements of those collision models has also resulted from this study.