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Detailed photographic mappings are presented for 33 early-type E and S0 galaxies in the Virgo cluster which are brighter than 14 mag. The mappings are based on B-band CCD and large-field photographic material. Attention is given to the geometrical characteristics of the isophotes in order to establish whether a faint disk is present, and the

Narrow-band H-alpha images and long-slit spectroscopy of the Seyfert galaxy NGC 985 are presented. Large-scale extended ionized zones are seen to cover a significant fraction of the ring of this object. These ionized zones are responsible for a considerable fraction (greater than 35 percent) of the far-infrared emission of NGC 985. These ionized

A generalized formulation of stellar speckle interferometry (SSI) and related techniques in terms of joint spatial/spatial-frequency energy representations are proposed. It is shown how, within this formulation, techniques such as that of Knox-Thompson, or even standard SSI, appear to be particular implementations of a more general method. This

In this paper we present the Johnson-Cousins UBVR CCD photometry of the stars in King 2, an old open cluster towards the galactic anticenter. We have obtained the colour- magnitude diagram, the colour excess, the reddening, an estimate of the metallicity, and the distance modulus. The comparison of the observational colour- magnitude diagram with

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