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Scientific achievements, Metagalaxy sector

Confirmation of the supercritical nature of the object NGC4395 X-1
With the 6-m SAO RAS telescope, the authors obtained the spectra of the optical counterpart of the ultraluminous X-ray object NGC4395 ULX-1. It is one of the faintest ULX objects (23 magnitudes), its optical spectrum has a broad HeII emission. All other spectra of the ULX ever obtained in the world (8) also have this line. This confirms the presence of supercritical accretion disks in the ULX objects of the same type as SS433 and in the new object NGC4395 ULX-1. Using the data obtained at the Swift/XRT observatory (observations from December 2005 to April 2015), the authors detected periodicity with a period of 62.8 days for NGC4395 ULX-1 in the X-ray range. The phase curve corresponding to this period has the characteristic shape of the main and secondary maxima and is very similar to the precession phase curve of SS433 (with a period of 162.3 days).
Authors:
Fabrika S.N., Vinokurov A.S., Atapin K.E.
Published:
Vinokurov, A.; Fabrika, S.; Atapin, K., Optical Counterparts of Ultraluminous X-Ray Sources NGC 4559 X-10 and NGC 4395 ULX-1, 2018, Astrophysical Journal, 854, 2

First results at the 1-m Schmidt telescope: complete sample of quasars up to R_AB=23^m with 0.5 < Z < 2.2 in the field of SA68
Observations during a year of test operation of the 1-m Schmidt telescope of BAO confirmed the possibility of efficient selection of young stellar objects observed in the Hα and [SII] narrow-band filters and in the medium-band filter 7500Å. Using the observations in 5 broad-band filters (SDSS u, g, r, I, and z) and in 5 the medium-band filters (4000Å - 5000Å), the authors composed a complete (up to R_AB=23^m) quasar sample with 0.5 < Z < 2.2 (123 objects) in the field of SA68 of a size of about 1 square degree. Spectroscopy of 29 objects (19.5^m < R < 22^m) at the BTA has proved that 28 objects refer to quasars.
Authors:
Dodonov S.N., Kotov S.S.

Detection and study of an optical flare associated with the gamma-ray burst GRB160625B
In the night from 25 to 26 of June, 2016, the multi-channel system of wide-angle optical monitoring of the subsecond-time-resolution Mini-MegaTORTORA (MMT) detected bright optical flare of 8.8 magnitude which accompanied one of the brightest gamma-ray bursts - GRB160625B. This event was detected by the Fermi Gamma-ray Space Telescope as a weak impulse (precursor), at the coordinates of which the MMT automatically pointed. Actually, the gamma-ray burst took place in two minutes, and then the optical flare began, the light curve of which was registered by the Mini-MegaTORTORA system during 10 minutes.
Authors:
Beskin G.M., Karpov S.V., Biryukov A.V., Bondar S.F., Ivanov E.A., Katkova E.V., Orekhova N.V., Perkov A.V., Sasyuk V.V. (SAO RAS, Precision Systems & Instruments Corp., "Arkhyz" optical observation station, "Parallax", LLC, Kazan Federal University)

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