Formation and evolution of dwarf elliptical galaxies: Structural and kinematical properties

We confront predictions of the currently popular theories for dE formation and evolution with the observed position of dEs in log L_B vs. log σ, log L_B vs. log R_e, log L_B vs. log I_e, and log R_e vs. log I_e diagrams and in the (log σ,log R_e,log I_e) parameter space in which bright and intermediate-luminosity elliptical galaxies and bulges of spirals define a Fundamental Plane (FP). We show that the dE sequences in the various univariate diagrams are disjunct from those traced by bright and intermediate-luminosity elliptical galaxies and bulges of spirals. It appears that semi-analytical models (SAMs) that incorporate quiescent star formation with an essentially z-independent star-formation efficiency, combined with post-merger starbursts and the dynamical response after supernova-driven gas-loss, are able to reproduce the position of the dEs in the various univariate and bivariate diagrams.