[89.06] Internal Kinematics, Ages and Metallicities of dE/dS0 Galaxies in the Coma Cluster

AAS 207th Meeting, 8-12 January 2006
Session 89 Dwarf Galaxies: Stellar Distributions and Star Formation
Oral, Tuesday, 10:00-11:30am, January 10, 2006, Salon 3

Previous | Session 89 | Next | Author Index | Block Schedule

[89.06] Internal Kinematics, Ages and Metallicities of dE/dS0 Galaxies in the Coma Cluster

A. Matkovic, R. Guzmán (University of Florida)

We present velocity dispersion and line strength index measurements for ~70 early--type galaxies in the core of the Coma cluster, including ~40 dwarf galaxies (dE/dS0). The luminosity-velocity dispersion (L--\sigma) relation for early--type galaxies in our sample exhibits a change of slope. Luminous early--type galaxies follow the canonical L \propto \sigma⁴ relation, while the slope of this relation for dE/dS0s is L \propto \sigma². We investigate rotation as a possible cause for the change of slope, but find its effect to be negligible. Using line index measurements combined with stellar population synthesis models, we find that dE/dS0 galaxies in the center of the Coma cluster span a wide range both in age and in metallicity. We also discuss the presence of a number of old, very metal--poor dwarf galaxies in our sample.

Previous | Session 89 | Next