Absorption line-strengths have allowed us to carry out a comprehensive stellar populations analysis, providing very strong constraints for discriminating and constraining current galaxy formation scenarios. I describe the main features of this approach, pinpointing the most popular indices and diagnostic diagrams, and the main problems affecting

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Deep observations of the dwarf elliptical (dE) galaxy NGC 1396 (MV = -16.60, Mass ˜4 × 108 M⊙), located in the Fornax cluster, have been performed with the Very Large Telescope/Multi Unit Spectroscopic Explorer spectrograph in the wavelength region from 4750 to 9350 Å. In this paper, we present a stellar population analysis studying chemical

We present the initial results of a study aimed at: (1) determining the lifetime of the disk accretion phase among low mass pre-main sequence stars; (2) establishing the time dependence of disk mass accretion rates; and (3) further exploring the role played by accretion disks in regulating stellar rotation. Our laboratory for this study is NGC 2264

The photoionization of extended narrow-line regions in Seyfert galaxies by the radiation produced in a thick accretion disk is studied. The emission-line spectrum is calculated for a range of black hole masses, varying the values of the ionization parameter and the disk size. It is found that models with a million solar masses fit observations of

Studies of Galactic chemical, and dynamical evolution in the solar neighborhood depend on the availability of precise atmospheric parameters (effective temperature T eff, metallicity [Fe/H], and surface gravity log g) for solar-type stars. Many large-scale spectroscopic surveys operate at low to moderate spectral resolution for efficiency in