No Arabic abstract
Here we present the spectropolarimetric observations of the radio loud active galaxy 3C 390.3 in the period 2009-2014 (24 epochs). The galaxy has been observed with the 6-meter telescope of SAO RAS using the SCORPIO spectropolarimeter. We explore the variability and lags in the polarized light of the continuum and broad H$alpha$ line. We give the Stokes parameters $Q, U$, degree of linear polarization $P$ and the position angle of the polarization plane, $varphi$, for 24 epochs. We find a small lag~(10-40 days) between the unpolarized and polarized continuum that is significantly smaller than the estimated lags for the unpolarized broad emission lines (lag(H$alpha$)$sim$138-186 and lag(H$beta$)$sim$60-79 days). This shows that the region of the variable polarized continuum is significantly smaller than the broad line region, indicating that a part of the polarized continuum is coming from the jet. The lag of the polarized light in the H$alpha$ line (89-156 days) indicates an additional component to the disc one that has an outflowing velocity of $sim$-1200 km s$^{-1}$. This region seems to depolarize the polarized broad H$alpha$ line emitted from the disc and scattered in the inner part of the torus.
We present new spectroscopic and polarimetric observations of the gravitational lens SDSS J1004+4112 taken with the 6m telescope of the Special Astrophysical Observatory (SAO, Russia). In order to explain the variability that is observed only in the blue wing of the C IV emission line, corresponding to image A, we analyze the spectroscopy and polarimetry of the four images of the lensed system. Spectra of the four images were taken in 2007, 2008, and 2018, and polarization was measured in the period 2014-2017. Additionally, we modeled the microlensing effect in the polarized light, assuming that the source of polarization is the equatorial scattering in the inner part of the torus. We find that a blue enhancement in the CIV line wings affects component A in all three epochs. We also find that the UV continuum of component D was amplified in the period 2007-2008, and that the red wings of CIII] and CIV appear brighter in D than in the other three components. We report significant changes in the polarization parameters of image D, which can be explained by microlensing.Our simulations of microlensing of an equatorial scattering region in the dusty torus can qualitatively explain the observed changes in the polarization degree and angle of image D. We do not detect significant variability in the polarization parameters of the other images (A, B, and C), although the averaged values of the polarization degree and angle are different for the different images. Microlensing of a broad line region model including a compact outflowing component can qualitatively explain the CIV blue wing enhancement (and variation) in component A. However, to confirmed this hypothesis, we need additional spectroscopic observation in future.
The scanning Fabry-Perot interferometer (FPI) - is the oldest method of optical 3D spectroscopy. It is still in use because of the high spectral resolution it provides over a large field of view. The history of the application of this method for the study of extended ob jects (nebulae and galaxies) and the technique of data reduction and analysis are discussed. The paper focuses on the performing observations with the scanning FPI on the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences (SAO RAS). The instrument is currently used as a part of the SCORPIO-2 multimode focal reducer. The results of studies of various galactic and extragalactic objects with the scanning FPI on the 6-m telescope - star-forming regions and young stellar objects, spiral, ring, dwarf and interacting galaxies, ionization cones of active galactic nuclei, galactic winds, etc. are briefly discussed. Further prospects for research with the scanning FPI of the SAO RAS are discussed.
This paper describes the aims, objectives and first results of the observational program for the study of distant core-collapse supernovae (SNe) with redshifts z < 0.3. This work is done within the framework of an international cooperation program on the SNe monitoring at the 6-m BTA telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences, and other telescopes. We study both the early phases of events (SN type determination, redshift estimation, and a search for manifestations of a wind envelope), and the nebular phase (the effects of explosion asymmetry). The SNe, associated with cosmic gamma-ray bursts are of particular interest. An interpretation of our observational data along with the data obtained on other telescopes is used to test the existing theoretical models of both the SN explosion, and the surrounding circumstellar medium. In 2009 we observed 30 objects; the spectra were obtained for 12 of them. We determined the types, phases after maximum, and redshifts for five SNe (SN 2009db, SN 2009dy, SN 2009dw, SN 2009ew, SN 2009ji). Based on the obtained photometric data a discovery of two more SNe was confirmed (SN 2009bx and SN 2009cb). A study of two type II supernovae in the nebular phase (SN 2008gz and SN 2008in) is finalized, four more objects (SN 2008iy, SN 2009ay, SN 2009bw, SN 2009de) are currently monitored.
We present the results of our spectropolarimetric observations for a number of active galactic nuclei (AGNs) carried out at the 6-m telescope with the SCORPIO focal reducer. The derived wavelength dependences of the polarization have been analyzed by taking into account the Faraday rotation of the polarization plane on the photon mean free path in a magnetized accretion disk. As a result, based on traditional accretion disk models, we have determined the magnetic field strength and distribution and a number of physical parameters of the accreting plasma in the region where the optical radiation is generated.
A detailed study of comets active at large heliocentric distances (greater than 4 au) which enter the Solar System for the first time and are composed of matter in its elementary, unprocessed state, would help in our understanding of the history and evolution of the Solar System. In particular, contemporary giant planet formation models require the presence of accretion of volatile elements such as neon, argon, krypton, xenon and others, which initially could not survive at the distances where giant planets were formed. Nevertheless, the volatile components could be effectively delivered by the Kuiper-belt and Oort-cloud bodies, which were formed at temperatures below 30 K. This review is dedicated to the results of a multi-year comprehensive study of small bodies of the Solar System showing a comet-like activity at large heliocentric distances. The data were obtained from observations with the 6-meter telescope of SAO RAS equipped with multi-mode focal reducers SCORPIO and SCORPIO-2.