Abstract. Here we present the results of panoramic and long-slit observations of eight ULX nebular counterparts held with the 6m SAO telescope. In two ULXNe we detected for the first time signatures of high excitation ([O iii]λ5007 / Hβ > 5). Two of the ULXs were identified with young (T ∼ 5 − 10 M yr) massive star clusters. Four of the eight ULX Nebulae (ULXNe) show bright high-excitation lines. This requires existence of luminous (∼ 10 38 ÷ 10 40 ergs s −1 ) UV/EUV sources coinciding with the X-ray sources. Other 4 ULXNe require shock excitation of the gas with shock velocities of 20-100km s −1 . However, all the studied ULXN spectra show signatures of shock excitation, but even those ULXNe where the shocks are prevailing show presence of a hard ionizing source with the luminosity at least ∼ 10 38 ergs s −1 . Most likely shock waves, X-ray and EUV ionization act simultaneously in all the ULXNe, but they may be roughly separated in two groups, shock-dominated and photoionization-dominated ULXNe. The ULXs have to produce strong winds and/or jets powering their nebulae with ∼ 10 39 ergs s −1 . Both the wind/jet activity and the EUV source needed are consistent with the suggestion that ULXs are high-mass X-ray binaries with the supercritical accretion disks of the SS433 type.

Abstract. We present BV RcIc broad-band flux spectra for the host galaxies of GRB 970508, GRB 980613, GRB 980703, GRB 990123 and GRB 991208 obtained with the 6-m telescope of SAO RAS. The comparison of the broad-band flux spectra of these host galaxies with the template spectral energy distributions (SEDs) of local starburst galaxies of different morphological types shows that the BV RcIc of the hosts are best fitted by the spectral properties of template SEDs of starburst galaxies and that there is a significant internal extinction in these host galaxies. We derived the absolute magnitudes of the GRB host galaxies making use of SEDs for the starburst galaxies. To create theoretical templates we performed the population synthesis modeling of the continuum spectral energy distribution of the host galaxies of GRB 970508 and GRB 980703 using different extinction laws (Cardelli et al. 1989 andCalzetti et al. 2000) and assuming burst and exponential scenarios of star formation. The comparison of BV RcIc broad-band flux spectra with the local starburst galaxies templates and theoretical templates as well as direct estimates (using Balmer emission lines) of the internal extinction shows that it is likely to be of great importance to take into account effects of the internal extinction in the host galaxies. From the energy distribution in the spectrum of the host galaxy of GRB 991208 and from the intensity of their spectral lines (with allowance for the effects of internal extinction) it follows that this is a GRB galaxy with the highest massive star-formation rate of all known GRB galaxies -up to hundreds of solar masses per year. The reduced luminosity of these dusty galaxies (e.g. for the host of GRB 970508 AV ∼ 2 mag, for the host of GRB 980703 AV ∼ 0.6 mag and for the host of GRB 991208 AV ∼ 2 mag) could explain the observational fact (it results independently from our BV RcIc photometry and from calculated spectral distribution for the subset of galaxies having been observed with the 6-m telescope): none of the observed GRB host galaxies with known distances is brighter than the local galaxies with the luminosity L * (where L * is the "knee" of the local luminosity function).

Here we present the long-term optical spectral monitoring of a changing-look active galactic nuclei (AGN) NGC 3516 that covers 22 years (from 1996 to 2018). We explore a variability in the broad lines and continuum, finding that the continuum is changing by more than a factor of 2, while the broad lines are varying by more than a factor of 10. The minimum of activity is observed in 2014, when the broad lines almost disappeared. We confirm that NGC 3516 is a changing-look AGN, and the absorption seen in the UV and X-ray may indicate that there is an obscuring region which is responsible for this.The line profiles are also changing. The mean profiles of the broad Hα and Hβ lines show shoulder-like structure in the wings, and enhanced peak, that may indicate a complex BLR. The rms-profiles of both lines seem to have the same shape and width of around 4200 km s −1 , indicating practically the same kinematics in the Hα and Hβ emitting regions.Measured time-lags between the continuum and Hα and Hβ broad-line variability are ∼ 15 and 17 days, respectively, that in combination with the broad lines width allows us to estimate the NGC 3516 central black hole mass. We find that the black hole mass is (4.73±1.40)×10 7 M ⊙ which is in agreement with previous estimates.

We present the first 3D observations of a diffuse elliptical galaxy (dE). The good quality data (S/N up to 40) reveal the kinematical signature of an embedded stellar disc, reminiscent of what is commonly observed in elliptical galaxies, though similarity of their origins is questionable. Colour map built from Hubble Space Telescope Advanced Camera for Surveys (ACS) images confirms the presence of this disc. Its characteristic scale (about 3 arcsec =250 pc) is about a half of galaxy's effective radius, and its metallicity is 0.1–0.2 dex larger than the underlying population. Fitting the spectra with synthetic single stellar populations (SSP), we found an SSP‐equivalent age of 5 Gyr and nearly solar metallicity [Fe/H]=−0.06 dex. We checked that these determinations are consistent with those based on Lick indices, but have smaller error bars. The kinematical discovery of a stellar disc in dE gives additional support to an evolutionary link from dwarf irregular galaxies due to stripping of the gas against the intracluster medium.

Context. The innermost regions in active galactic nuclei (AGNs) were not being spatially resolved so far but spectropolarimetry can provide us insight about their hidden physics and the geometry. From spectropolarimetric observations in broad emission lines and assuming equatorial scattering as a dominant polarization mechanism, it is possible to estimate the mass of supermassive black holes (SMBHs) residing in the AGN center. Aims. We explore the possibilities and limits and put constraints on the usage of the method for determining SMBH masses using polarization in broad emission lines by providing more in-depth theoretical modeling. Methods. We use the Monte Carlo radiative transfer code stokes for exploring polarization properties of Type 1 AGNs. We model equatorial scattering using flared-disk geometry for a set of different SMBH masses assuming Thomson scattering. In addition to the Keplerian motion which is assumed to be dominant in the broad line region (BLR), we also consider cases of additional radial inflows and vertical outflows. Results. We model the profiles of polarization plane position angle ϕ, degree of polarization and total unpolarized line for different BLR geometries and different SMBH masses. Our modeling confirms that the method can be widely used for Type-1 AGNs when viewing inclinations are between 25• and 45• . We show that the distance between the BLR and scattering region (SR) has a significant impact on the mass estimates and the best mass estimates are when the SR is situated at the distance 1.5-2.5 times larger than the outer BLR radius. Conclusions. Our models show that if Keplerian motion can be traced through the polarized line profile, then the direct estimation of the mass of the SMBH can be performed. When radial inflows or vertical outflows are present in the BLR, this method can still be applied if velocities of the inflow/outflow are less than 500 km s −1 . We also find that models for NGC 4051, NGC 4151, 3C 273 and PG0844+349 are in good agreements with observations.

We have obtained and analyzed long-slit spectral data for the lenticular galaxy IC 719. In this gas-rich S0 galaxy, its large-scale gaseous disk counterrotates the global stellar disk. Moreover in the IC 719 disk we have detected a secondary stellar component corotating the ionized gas. By using emission-line intensity ratios, we have proved the gas excitation by young stars and so are claiming current star formation, most intense in a ring-like zone at the radius of 10 ′′ (1.4 kpc). The oxygen abundance of the gas in the starforming ring is about half of the solar abundance. Since the stellar disk remains dynamically cool, we conclude that smooth prolonged accretion of the external gas from a neighboring galaxy provides current building of the thin large-scale stellar disk.

We describe the technique of spectropolarimetric observations allowing for the measurements of the Stokes parameters in one of the observational modes of the SCORPIO focal reducer of the 6-m BTA telescope of the SAO RAS. The characteristics of the instrument in the spectropolarimetric mode of observations are given. We present the algorithm of observational data reduction. The capabilities of the SCORPIO spectropolarimetric mode are demonstrated on the examples of observations of various astronomical objects.

We present measurements of ages, metallicities and [α/Fe] ratios for 16 globular clusters (GCs) in NGC 147, 185 and 205 and of the central regions of the diffuse galaxy light in NGC 185 and 205. Our results are based on spectra obtained with the SCORPIO multislit spectrograph at the 6-m telescope of the Russian Academy of Sciences. We include in our analysis highquality Hubble Space Telescope/WFPC2 photometry of individual stars in the studied GCs to investigate the influence of their horizontal branch (HB) morphology on the spectroscopic analysis. All our sample GCs appear to be old (T > 8 Gyr) and metal-poor ([Z/H] −1.1), except for the GCs Hubble V in NGC 205 (T = 1.2 ± 0.6 Gyr, [Z/H] = −0.6 ± 0.2), Hubble VI in NGC 205 (T = 4 ± 2 Gyr, [Z/H] = −0.8 ± 0.2) and FJJVII in NGC 185 (T = 7 ± 3 Gyr, [Z/H] = −0.8 ± 0.2). The majority of our GCs sample has solar [α/Fe] enhancement in contrast to the halo population of GCs in M31 and the Milky Way.The HB morphologies for our sample GCs follow the same behaviour with metallicity as younger halo Galactic GCs. We show that it is unlikely that they bias our spectroscopic age estimates based on Balmer absorption-line indices. Spectroscopic ages and metallicities of the central regions in NGC 205 and 185 coincide with those obtained from colour-magnitude diagrams. The central field stellar populations in these galaxies have approximately the same age as their most central GCs (Hubble V in NGC 205 and FJJIII in NGC 185), but are more metal-rich than the central GCs.