We have obtained radial velocities of 68 planetary nebulae (PNs) surrounding the SB0 galaxy NGC 3384 in the Leo I group, using the CTIO 4 m telescope and the Rutgers Fabry-Perot interferometer. The PN system exhibits a well-ordered rotation field aligned with the photometric axes of the galaxy. The rotation curve is flat from about 2 kpc until at least 7 kpc. We infer a lower limit of 0.7 x 10 11M. for the mass of NGC 3384. Our results imply that at least a third of the dynamical mass of the NGC 3379/3384 system -- estimated by Schneider (1985) to be roughly 6 x 10 11M. -- may be accounted for in the two bright galaxies. (Refer to PDF file for exact formulas).
Department, Program, or Center
School of Physics and Astronomy (COS)
Astrophysical Journal Letters 443 (1995) L5
RIT – Main Campus