Andrievsky S.M., Korotin S.A., Hill V., Zhukova A.V. «Zirconium abundances in the central part of the DsPH Fornax galaxy» Публикации Одесской астрономической обсерватории (Odessa Astronomical Publications, Украина), 30, с. 54-56 (2017)

DOI: https://doi.org/10.18524/1810-4215.2017.30.117154 We derived LTE zirconium abundance in a sample of 81 giant stars in dwarf spheroidal Fornax galaxy. The LTE synthesis was used for this aim. We obtained the lower Zr abundance in Fornax galaxy comparing to the relevant value in the thick/thin disc of the Milky Way. We note that this result may be affected by the NLTE effects that decrease the real zirconium abundance.

Holovko M.G., Gladush V.D. «Quantization of the spherically symmetric configuration of the gravitational and electromagnetic fields» Публикации Одесской астрономической обсерватории (Odessa Astronomical Publications, Украина), 30, с. 23-26 (2017)

DOI: https://doi.org/10.18524/1810-4215.2017.30.114223 To construct a quantum model of a charged black hole (CBH), we introduce a modified description of the configuration of the electromagnetic and gravitational fields in a spherically symmetric space-time, which consists of T- and R- regions. We choose such coordinate system that the desired metric functions depend only on the time coordinate in the T-region, and on the space coordinate in the R-region. Then, the initial action for the configuration decays into terms which describe the fields in the T- and R-regions with the time and the space evolutionary coordinate respectively. We define new coordinates in the R- and T- regions, what allows us to unify the form of the Lagrangians, in each of them and carry out their uniform analysis. Then we construct the canonical formalism for obtained degenerate system according to the method of D.M. Gitman and I.V. Tyutin. It appears that system contains non-physical degrees of freedom. For their expicit separation we carry out the canonical transformation to new canonical variables. In these variables the constraints are reduced to the canonical form and physical part of the Hamilton function of the system is identically equal to zero. This leads to the fact that the desired wave function is determined only by the eigenvalue equations for the operators of observable physical quantities. According that considered system has only two observables – charge and mass of black hole – for further construction of quantum model of this system we introduce its mass and charge functions and find their expression in the new canonical variables. The solution of eigenvalue equations for corresponding operators leads to continuous spectra of charge and mass in considered model of CBH.

Oknyansky V.L., Gaskell C.M., Huseynov N.A., Mikailov Kh.M., Lipunov V.M., Malanchev N.I., Tsygankov S.S., Gorbovskov E.S., Tatarnikov A.M., Metlov V.G., Shatsky K.L., Brotherton M.B., Kasper D., Du P., Chen X., Burlak M.A., Buckley D.A.H., Rebolo R., Serra-Ricart M., Podesta R., Levato H. «Ulti-wavelength monitoring of the changing-look AGN NGC 2617 during state changes» Публикации Одесской астрономической обсерватории (Odessa Astronomical Publications, Украина), 30, с. 117-120 (2017)

DOI: https://doi.org/10.18524/1810-4215.2017.30.114366 Optical and near-infrared photometry, optical spectroscopy, and soft X-ray and UV monitoring of the changing-look active galactic nucleus NGC 2617 show that it continues to have the appearance of a type-1 Seyfert galaxy. An optical light curve for 2010–2017 indicates that the change of type probably occurred between 2010 October and 2012 February and was not related to the brightening in 2013. In 2016 and 2017 NGC 2617 brightened again to a level of activity close to that in 2013 April. However, in 2017 from the end of the March to end of July 2017 it was in very low level and starting to change back to a Seyfert 1.8. We find variations in all passbands and in both the intensities and profiles of the broad Balmer lines. A new displaced emission peak has appeared in H_β. X-ray variations are well correlated with UV–optical variability and possibly lead by ∼2–3^d. The K band lags the J band by about 21.5±2.5^d and lags the combined B+J bands by ∼25^d. J lags B by about 3 d. This could be because J-band variability arises predominantly from the outer part of the accretion disc, while K-band variability is dominated by thermal re-emission by dust. We propose that spectral-type changes are a result of increasing central luminosity causing sublimation of the innermost dust in the hollow bi-conical outflow. We briefly discuss various other possible reasons that might explain the dramatic changes in NGC 2617.