Hubble Space Telescope Photometry of the Central Regions of Virgo Cluster Elliptical Galaxies. I. Observations, Discussion, and Conclusion

Abstract

Using the Hubble Space Telescope we have observed at 10 pc resolution the nuclei of a luminosity-limited sample of 14 E and E/S0 galaxies in the Virgo Cluster with magnitudes B_T_ = 9.4 to 13.4. In this paper we present the images, and discuss the results of the detailed analysis of the surface photometry given in two companion papers. We find that the nuclear and near-nuclear morphologies confirm and strengthen the previously recognized dichotomy of "E" galaxies into "true" and "disky" subtypes. The latter, usually classified E4 or later, often show a bright nuclear disk of radius ~100 pc. Essentially all early-type galaxies with -18 > M_B_ > -20 are disky. Most true E galaxies are classified E4 or earlier. Most galaxies of both types show dust in the nuclear regions, the most remarkable example being a compact dust disk in NGC 4261. Other than dust, no anomalies were detected in the centers of the three galaxies in our sample which show clear kinematic evidence for a decoupled component.