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The morphologies of the 96 dwarf (M(B) ≥ -17m) galaxies in the Markarian catalog are determined from the digitized Schmidt plates obtained for the construction of the Hubble Space Telescope Guide Star Catalog. The fraction of double nucleus galaxies within the dwarf Markarian galaxies is determined to be twice that found for all galaxies in the Markarian catalog. In addition to the 12 previously known cases, four definite and two probable galaxies with double nuclei are identified. The fraction of dwarf Markarian galaxies with bright star forming regions is found to be twice that of Virgo cluster dwarf galaxies. No Elliptical galaxies are found in the sample. Galaxies with blue compact dwarf and S0 morphologies are more often found to contain unresolved regions of UV excess emission. Dwarf Markarian galaxies with different morphological structures and spectral classes are found to have similar FIR properties.

Wide Field Camera 3 (WFC3), a panchromatic imager being developed for the Hubble Space Telescope (HST), is now fully integrated and has undergone extensive ground testing at Goddard Space Flight Center, in both ambient and thermal-vacuum test environments. The thermal-vacuum testing marks the first time that both of the WFC3 UV/Visible and IR channels have been operated and characterized in flight-like conditions. The testing processes are completely automated, with WFC3 and the optical stimulus that is used to provide external targets and sources being commanded by coordinated computer scripts. All test data are captured and stored in the long-term Hubble Data Archive. A full suite of instrument calibration tests have been performed, including measurements of detector properties such as dark current, read noise, flat field response, gain, linearity, and persistence, as well as total system throughput, encircled energy, grism dispersions, IR thermal background, and image stability tests. Nearly all instrument characteristics have been shown to meet or exceed expectations and requirements. Solutions to all issues discovered during testing are in the process of being implemented and will be verified during future ground tests.

Galaxies with box/peanut-shaped (b/p) bulges have been known for some time (e.g., NGC 128 and NGC 7332 (Sandage 1961)). Observationally, b/p features are detected in edge-on systems, and are visible in images, contour maps, and brightness profiles as isophote sections that near minor axis are relatively flat and parallel to major axis (see Figure 1). Peanut-type bulges have isophotes indented at the intersection with the minor axis.There have been several morphological surveys to date. The two most recent studies have found that about 20% of early-type galaxies and nearly 45% of all disk galaxies are b/p galaxies (see Shaw 1987, Dettmar 1989, and references therein) and that the b/p galaxy properties appear similar to normal spirals in the optical, radio, and infrared. A few kinematical studies have been done: b/p bulges are found to rotate more like disks than bulges (e.g., 150 km s−1 up to 6 kpc above the plane in NGC 128 (Jarvis 1990) and the velocities remain constant up to large z, implying cylindrical rotation (e.g., NGC 3079 has v constant out to 1.6 kpc (Shaw et al. 1993)).

We present the data and initial results from a combined Hubble Space Telescope (HST)/IUE/ground-based spectroscopic monitoring campaign on the Seyfert 1 galaxy NGC 5548 that was undertaken in order to address questions that require both higher temporal resolution and higher signal-to-noise ratios than were obtained in our previous multiwavelength monitoring of this galaxy in 1988-1989. IUE spectra were obtained once every 2 days for a period of 74 days beginning on 1993 March 14. During the last 39 days of this campaign, spectroscopic observations were also made with the HST Faint Object Spectrograph (FOS) on a daily basis. Ground-based observations, consisting of 165 optical spectra and 77 photometric observations (both CCD imaging and aperture photometry), are reported for the period 1992 October-1993 September, although many of the data are concentrated around the time of the satellite-based program. These data constitute a fifth year of intensive optical monitoring of this galaxy. In this contribution we describe the acquisition and reduction of all of the satellite and ground-based data obtained in this program. We describe in detail various photometric problems with the FOS and explain how we identified and corrected for various anomalies.

New data are presented for IRAS 0421+040P06 and NGC 6240. These two galaxies have properties that differ from both Seyfert and starburst galaxies.

Cette caracteristique est visible sur les images CCD obtenues avec des filtres a bande etroite centres sur les raies [OIII] et Hα decalees vers le rouge, mais pas en lumiere continue. La source de son ionisation doit se trouver dans le noyau. Il se pourrait qu'elle resulte de l'interaction avec une autre galaxie

The IRAS source 04210+0400 coincides with a galaxy that exhibits strong double-lobed radio emission extending 15 kpc outside the optical galaxy. New high-resolution radio maps reveal a classical low-luminosity double radio structure and an extended nuclear source that is aligned toward a hot spot in one of the lobes. Visible spectroscopy shows that the light from the features that were originally thought to be spiral arms is neither starlight nor light scattered from the nucleus; the spectra show strong emission lines whose relative intensity, radial velocity, and velocity dispersions vary with position. The data suggest that the extended spiral features are photoionized remnants of earlier radio jet activity and that the unusual properties of this object might be characterized as those of a radio galaxy that has an unusually high dust content and a strong source of ultraviolet radiation at its core. The nuclear activity may be related to an interaction with a nearby companion galaxy. 19 references.