Studying the chemical compositions and color-magnitude diagrams of globular clusters in the nearby low-mass galaxies is critical to compare properties of these long-living objects situated in galaxies of different type and mass, and to establish the role of dwarf galaxies as building blocks of massive early-type and spiral galaxies. We present measurements of ages, metallicities and [α/Fe] ratios for 16 globular clusters (GC) in NGC147, NGC185, and NGC205 and for the central regions of the diffuse galaxy light in NGC185, and NGC205, based on measurements of absorption line indices as defined by the Lick standard system in spectra obtained with the SCORPIO multi-slit spectrograph at the 6-m telescope of the Russian Academy of Sciences. We include in our analysis high-quality HST/WFPC2 photometry of individual stars in the GGs to investigate the influence of their horizontal branch (HB) morphology on the spectroscopic analysis. The HB morphologies for our sample GCs follow the same behavior with metallicity as younger halo Galactic globular clusters. We show that it is unlikely that they bias our spectroscopic age estimates based on Balmer absorption-line indices. Almost all our sample GCs appear to be old (T > 8 Gyr) and metal-poor ([Z/H]<−1.1). We find that most of the GCs in the studied galaxies are weakly or not α-enhanced, in contrast to the population of GCs in nearby early-type galaxies, and to the halo population of GCs in M31 and Milky Way.

We study properties of globular cluster candidates (GCCs) and the diffuse stellar populations in nearby low surface brightness dwarf galaxies, using HST WFPC2 photometry in the V and I bands. Our sample consists of 18 dwarf spheroidal (dSph), 36 dwarf irregular (dIrr), and 3 transition-type galaxies, with projected linear diameters less than 3.5 kpc and mean blue surface brightness $>23$ mag/arcsec$^2$ situated at the distance 2–6 Mpc in the field and in nearby groups. Our sample dwarf spheroidal galaxies were not detected in HI and are located at the distances of up to $\sim$1 Mpc away from a nearby bright galaxy. Transition-type galaxies, which are distributed like dSph galaxies, form a very rare class of galaxies. dIrr galaxies show a weaker concentration to the nearest massive neighbors than dSph and transition-type galaxies. At a given surface brightness and luminosity, they exhibit lower mean metallicities than dSphs. In contrast to dIrr galaxies, the majority of dSph galaxies at a similar mean surface brightness contains GCCs. The percentage of GCCs located near the centers of dSph galaxies is much higher than that for dIrr galaxies. The composite population of GCCs in dSphs is spatially more concentrated than in dIrr galaxies. The color distributions of GCCs in dSph and dIrr galaxies show major differences. While the latter shows obvious bimodality with the peaks near $(V-I)_0 \sim 0.5$ and $\sim$1.0 mag, the GCC color distribution in dSph galaxies shows only one peak with a mean color $(V-I)_0 \sim 1.0$ mag. There is a tendency of increasing half-light radii with increasing projected galactocentric distances for a large number of GCCs in dSph galaxies, which is also observed in the Galactic globular cluster system. We embarked on a spectroscopic survey of GCCs in low-mass galaxies to obtain their chemical compositions and relative ages.

During the last decades many authors have concentrated their efforts on understanding what are the most efficient mechanisms to feed an AGN. Several solutions have been proposed, as the presence of circumnuclear star clusters, nuclear bars/disks/spirals, and the interaction between galaxies, in form of close encounters and mergers. Here we present new results about an isolated, intermediate-type Seyfert galaxy, Mrk315. The analysis of broad- and narrow-band images, and integral field spectra revealed a spiral-like structure hidden under the E/S0 morphology of the galaxy, and confirmed the presence of a nuclear jet-like feature, forming a sort of very extended “hook”. Moreover, our data confirmed the supposed nature of the already known knot, located at 2” from the active nucleus, as a secondary nucleus, residual of a minor merger bewteen the galaxy and a small nucleated companion.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

Seyfert galaxies with Z-shaped emission filaments in the Narrow Line Region (NLR) are considered. We assume that observable Z-shaped structures and the velocity pattern of the NLR may be explained as tri-dimensional helical waves in the ionization cone.

It was noted at the earlier study and at the longer observations of the novel various types of superstoichiometric fluorocarbon materials CF1+x, where x = 0.1–0.33 (FCM) and their behavior, that despite of their known hygroscopity during a storage of samples in laboratory and technological utensils nevertheless occurs an appreciable sorption of atmospheric moisture. The color of samples does not change but sometimes there is appears a smell of hydrogen fluoride and even corrosion of glasswares at a long storage. On the basis of these facts was assumed that at a long storage the slow reactions of HF producing with a sorption moisture can proceed. This phenomena is necessary to take into account for successful manufacturing of long life lithium cells based on superstoichiometric fluorocarbon composite cathodes (FCC).

The Seyfert 2 galaxy Mrk 533 has the morphological description of SA(r)bc pec in RC3 and SBb in UGC. It is a member of the compact group of galaxies H96. Radio observations (Unger et al. 1988) show three radio sources.

3-D observations with a Fabry-Perot scanning interferometer (the number of spectral channels is 32 by 0.44 Å, angular size of 1 px is , the accuracy of radial velocity determination is 10 km s−1) and multi-pupil integral spectrograph observations (the dispersion is 1.16 Å px−1, lens array is 10×16, angular size of each lens is × ) were obtained in the red spectral range at the 6-m telescope. The estimated seeing was about 2″. In the central region of the galaxy (r ≥ 5″, interferometer observations) the Hα line profile was fitted by two Gaussians. The first component, Kl, corresponds to the galaxy disk. The second component, K2, is visible only in the central part and is brighter than K1 in the same pixels. Profiles of Hα and [NII] Λ6584/48 (integral spectroscopy observations) were fitted by two Gaussians. They are a broad component in Hα and [NII] with FWHM ~ 1000 km s−1 and a narrow component of three times less FWHM. The lower spectral resolution of this observation made it impossible to separate the narrow component into the two ones visible in the Fabry-Perot observations.

The central (8″ × 8″) regions of the Seyfert galaxies Mrk 744 and NGC 4151 were studied by the 3D-spectroscopy method. There is evidence that a mini-bar (0.5–2 kpc) is present in the central regions of these galaxies, which provides transportation of gas of the disk to fuel the nucleus.

Results of 3D-spectroscopy for the nearby Seyfert galaxy Mrk 573 obtained at the 6-m telescope with the scanning Fabry-Perot interferometer and the Multi-Pupil Field Spectrograph (MPFS) are presented. Emission lines images of the galaxy center demonstrate a complex structure of ENLR, coinciding with the radio data. An analysis of the velocity field shows that some gas structures do not lie in the plane of the galaxy. An explanation of the observed velocity field and gas distribution by radiation of a helical structure located inside an ionization cone is proposed.

Kinematic investigations of the central (10″×10″) regions of the Seyfert galaxies NGC 4151 and Mkn 573 on the 6-m telescope with 3D-spectroscopy methods are presented.

Degradation of images of astronomical objects during observations with large optical telescope may be described as combination of atmosphere turbulence on a time scale shorter than some tenths of a second and random fluctuation of object’s position due to telescope and observer’s guiding errors, bending of construction under external factors (wind, etc.). Special investigations on the 6-meter telescope (Balega, 1989) showed, that the peak frequency of such low-frequency fluctuations is located near 1 Hz.

The method of Time Resolving Image Mode, developed by J.-L.Nieto et al (1987) for post-detection improvement of angular resolution at CFHT, showed that, even in places with excellent quality of atmosphere, the resolution of large telescope may be increased by 20-30% only, although powerful methods of image recentering and frames selection were performed. Moreover, such method of data processing may be applied to relatively bright objects only. For 6-meter telescope, resolution improvement would be useless at all due to smaller Fried parameter and larger main mirror.

First attempts to get spectra from extended areas were in the middle of 80-th, using fibers techniques: DensePack (Barden, Scott, 1986), SILFID (Vanderriest and Lemonnier, 1988). Bundle of fibers were put at the focus of the telescope and the other ends of fibers rearranged to produce a long slit of the spectrograph.

Another method of bidimensional spectroscopy, not using optical fibers, was proposed by Prof. G. Courtes (Courtes et al, 1988). He recommended to put behind the telescope focal plane a bidimensional array of microlenses and to project on it an enlarged image. The lens array separates continuous input image and forms an array of micro-pupils that are images of the main mirror illuminating each lens. They create an input image for a classical spectrograph instead of a normal slit. Using of square lenses allows to achieve correct data sampling, and such scheme is ideal for spectrophotometry, allowing integration of total energy from the observed sky area.

Two independent fields of 14′ × 14′ south east of M82 and 7′ × 7′ in SA 57 were completely spectroscopicaly searched for quasars using the Multi Slit Field Spectrograph at the 6-meter telescope of the Academy of Sciences of the USSR (Dodonov, 1982).