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Scientific achievements, Metagalaxy sector

 2021: 


Discovery of new properties of the gravitationally lensed quasar Q0957+561
Gravitational lenses, responsible for the formation of multiple images of distant objects (usually galaxies and quasars), are often used in modern astrophysics to detect the large-scale distribution of matter in the Universe. However, the study of the lensed images themselves makes it possible to examine in more detail the structure of the central parsec of the spatially unresolved active nuclei using direct optical methods. During the observations of the lensed quasar Q0957+561 at the BTA of SAO RAS, it was first discovered that the polarization vector is oriented in different ways differently in two images of the source, and the polarization angle changes with wavelength. Previously, similar properties were not observed in gravitational objects. The effect can be described qualitatively by a lensing model of the accretion disk as an extensive source with the continuous polarization.
Authors: V.L. Afanasiev, E.S. Shablovinskaya (SAO RAS) in cooperation with L.C. Popovic, Dj. Savic (Astronomical Observatory in Belgrade, Serbia)
Published:
1. Popovic L.C., Afanasiev V.L., Shablovinskaya E.S., Ardilanov V.I., Savic D. Spectroscopy and polarimetry of the gravitationally lensed quasar Q0957+561, 2021, A&A, 647, A98. doi.org/10.1051/0004-6361/202039914


Search for "hibernating" active galactic nuclei by their ionization signs in the intergalactic medium
The study of the ionization state of gaseous clouds outside the galactic disks makes it possible to study the change in the intensity of ionizing radiation associated with the activity of the central supermassive black hole. For the first time, a search for such clouds has been performed in a complete luminosity-limited sample of nearby galaxies with active nuclei. Among 111 objects, the systems of ionized gas far from the nucleus (25-75 kpc) were found in 3 cases. It was found that the activity in NGC 5514 has more than 3 times decreased over the past 250 thousand years. Also, in 4 galaxies, giant (up to 10 kpc) ionization cones were found inside galactic disks. It is shown that in the overwhelming majority of objects, ionized clouds belong to tidal structures associated with the interaction of galaxies. The study of the state of gas ionization was carried out with the telescopes: BTA SAO RAS, 2.6-m KGO SAI MSU, and 1.6-m ISTP SB RAS using the instruments created at SAO RAS (SCORPIO-1/2, MaNGaL, ADAM).
Authors: Moiseev A.V., Kozlova D.V., Ikhsanova A.I., Oparin D.V., Uklein R.I. (SAO RAS) in cooperation with W.C. Keel (University of Alabama, USA), Eselevich M.V. (ISTP SB RAS)
Published:
1. Keel W.C., Moiseev A., Kozlova D.V., Ikhsanova A.I., Oparin D.V., Uklein R.I., Smirnova A.A., Eselevich M.V., The TELPERION Survey for Distant [O III] Clouds around Luminous and Hibernating AGN, Monthly Notices of the Royal Astronomical Society, 510, 3, 2022, 4608–4625, DOI: 10.1093/mnras/stab3656


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Last update: 29/11/2022