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https://dspace.onu.edu.ua/handle/123456789/13174

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Alignment of galaxies in subclustres placed in rich regions
(2019) Korshunov, V.; Panko, Olena O.; Панько, Елена Алексеевна; Панько, Олена Олексіївна
The study of galaxies orientation is one of standard tests of galaxies formation scenarios. In filaments and walls the elliptical and disc galaxies chow different orientations (Joachimi et al., 2015).
Analysis of near-earth resident space objects visibility conditions from optical ground stations
(2019) Shakun, Leonid S.; Korobeinikova, E. A.; Koshkin, Nikolay I.; Kozhukhov, O.; Kozhukhov, D.; Piskun, O.; Strakhova, Svitlana I.; Кошкін, Микола Іванович; Кошкин, Николай Иванович
The continuous monitoring of space object positions in near-Earth space is necessary for tasks of: -the collision prevention of an active satellite with other satellites or space debris objects; -the cleaning Near-Earth space from inactive satellites and space debris; -the planning of new satellite launches.
Astronegative archive of Odessa observatory. Large surveys with small telescopes
(2019) Kashuba, S. V.; Bazyey, N. V.; Kashuba, V. I.; Andrievsky, Serhii M.; Андрієвський, Сергій Михайлович; Андриевский, Сергей Михайлович
Currently Observatory of I. I. Mechnikov Odessa National University owns collections of astronegatives obtained with its own instruments (about 100000 glass plates), as well as those obtained with instruments from other observatories (about 10000 plates). According to Bulgarian web-page WFPDB (wfpdb.org) Odessa collection of astroplates is second in Europe (after Sonneberg collection) and third in the world (after Harvard and Sonneberg). In this poster we describe the current condition of our collection and consider our plans for how to maintain this important astronomical heritage. We are also discussing our first steps in digitizing part of a collection in accordance with the decision of the world virtual observatory and WFPDB standards.
Coopération Franco-Ukrainienne dans dans l'étude de l'évolution chimique de Notre Galaxie
(2019) Andrievsky, Serhii M.; Андрієвський, Сергій Михайлович; Андриевский, Сергей Михайлович
Notre Galaxie comprend différentes sous-structures : disques minces et épais, renflement, halo, etc. Ces sous-structures contiennent des étoiles de types différents, en particulier de niveau de métallicité différente. Une étude de la composition chimique de ces étoiles fournit une information cruciale sur l'évolution chimique de notre système stellaire dans son ensemble. Jusqu'à présent, nous n'avions pas de solution définitive au problème de la formation de la Voie Lactée : s'agit-il d'un processus hiérarchique allant de la grande structure aux plus petites sous-structures, ou bien notre galaxie s'est-elle formée à la suite de processus de fusion impliquant des systèmes stellaires plus petits, tels que des galaxies naines et des amas globulaires ? L'étude des propriétés chimiques des étoiles de différentes sous-structures de la Voie Lactée peut éclairer cette énigme astrophysique.
Dynamics of the asteroid rings (10199) Chariklo
(Одеський національний університет імені І. І. Мечникова, 2016) Troianskyi, V. V.; Bazyey, Oleksandr A.; Троянський, В. В.; Базєй, Олександр Анатолійович; Троянский, В. В.; Базей, Александр Анатолиевич
In 2014 it was reported on opening two rings around asteroid (10199) Chariklo (Braga-Ribas F., et al., 2014, Nature, 508, 72–75) and it became the fifth object of the Solar system known to have ring system, after Jupiter, Saturn, Uranus and Neptune. The main component of the system is the biggest Centaur. This work considers the erosion time of rings in the asteroid system (10199) Chariklo, that is due to a number of effects. Also, we have calculated the mass and period of rotation of the asteroid’s shepherd satellite.
Effect of peculiar velocities on the gravitational potential in cosmological models with perfect fluids
(2020) Burgazli, Alvina; Shulga, Valerii; Yükselci, A. Emrah; Zhuk, Oleksandr I.; Жук, Олександр Іванович; Жук, Александр Иванович
We consider a universe filled with perfect fluid with the constant equation of state parameter ω. In the theory of scalar perturbations, we study the effect of peculiar velocities on the gravitational potential. For radiation with ω=1/3, we obtain the expression for the gravitational potential in the integral form. Numerical calculation clearly demonstrates the modulation of the gravitational potential by acoustic oscillations due to the presence of peculiar velocities. We also show that peculiar velocities affect the gravitational potential in the case of the frustrated network of cosmic strings with ω=−1/3.
Effect of the Cubic Torus Topology on Cosmological Perturbations
(2021) Eingorn, Maxim; Canay, Ezgi; Metcalf, Jacob M.; Brilenkov, Maksym; Zhuk, Oleksandr I.; Жук, Олександр Іванович; Жук, Александр Иванович
We study the effect of the cubic torus topology of the Universe on scalar cosmological perturbations which define the gravitational potential. We obtain three alternative forms of the solution for both the gravitational potential produced by point-like masses, and the corresponding force. The first solution includes the expansion of delta-functions into Fourier series, exploiting periodic boundary conditions. The second one is composed of summed solutions of the Helmholtz equation for the original mass and its images. Each of these summed solutions is the Yukawa potential. In the third formula, we express the Yukawa potentials via Ewald sums. We show that for the present Universe, both the bare summation of Yukawa potentials and the Yukawa-Ewald sums require smaller numbers of terms to yield the numerical values of the potential and the force up to desired accuracy. Nevertheless, the Yukawa formula is yet preferable owing to its much simpler structure.
Effect of the spatial curvature of the Universe on the form of the gravitational potential
(2019) Eingorn, Maxim; Yükselci, A. Emrah; Zhuk, Oleksandr I.; Жук, Олександр Іванович; Жук, Александр Иванович
Within the cosmic screening approach, we obtain the exact formulas for the velocity-independent gravitational potentials produced by matter in the form of discrete sources distributed in the open and closed Universes. These formulas demonstrate that spatial curvature of the Universe considerably affect the form of the potentials and forces.While in the open Universe the gravitational force undergoes exponential suppression at cosmological distances, in the closed Universe the force induced by an individual mass is equal to zero at the antipodal point with respect to this mass. The derived formulas are applicable for investigations of the motion of astrophysical objects (e.g., galaxies) in the open and closed Universes, and for simulations of the large scale structure formation.
Effects of nonlinearity of f (R) gravity and perfect fluid in Kaluza–Klein models with spherical compactification
(2020) Canay, Ezgi; Eingorn, Maxim; Zhuk, Oleksandr I.; Жук, Олександр Іванович; Жук, Александр Иванович
We study the effects associated with nonlinearity of f (R) gravity and of the background perfect fluid manifested in the Kaluza–Klein model with spherical compactification. The background space-time is perturbed by a massive gravitating source which is pressureless in the external space but has an arbitrary equation of state (EoS) parameter in the internal space. As characteristics of a nonlinear perfect fluid, the squared speeds of sound are not equal to the background EoS parameters in the external and internal spaces. In this setting, we find exact solutions to the linearized Einstein equations for the perturbed metric coefficients. For nonlinear models with f (R0) = 0, we show that these coefficients acquire correction terms in the form of two summed Yukawa potentials and that in the degenerated case, the solutions are reduced to a single Yukawa potential with some “corrupted” prefactor (in front of the exponential function), which, in addition to the standard 1/r term, contains a contribution independent of the three-dimensional distance r . In the linear f (R) = 0 model, we generalize the previous studies to the case of an arbitrary nonlinear perfect fluid. We also investigate the particular case of the nonlinear background perfect fluid with zero speed of sound in the external space and demonstrate that a non-trivial solution exists only in the case of f (R0) = 0.
Gaia18aak is a new SU UMa-type dwarf nova
(2019) Simon, A.; Pavlenko, E.; Shugarov, S.; Vasylenko, V.; Izviekova, I.; Reshetnyk, V.; Godunova, V.; Bufan, Yu.; Baransky, A.; Antonyuk, O.; Baklanov, V.; Troianskyi, V.; Udovichenko, Serhii M.; Keir, L.; Удовіченко, Сергій Миколайович; Удовиченко, Сергей Николаевич
We report the discovery of a new SU UMa-type dwarf nova, Gaia18aak/ AT2018C, based on its optical observations, which were performed at ve observatories (Lisnyky/Kyiv, Terskol, CrAO, Mayaki/Odessa and Star a Lesn a, Slovakia) with six small telescopes. The observational campaign started just after the alert was published by ESA Gaia, DPAC and the Photomet- ric Science Alerts Team (http://gsaweb.ast.cam.ac.uk/alerts); the object was very intensely observed during the rst month. After this there was organized a four-month monitoring in order to test outburst activity of the object. We detected the 0.0647-d (or 0.0692-d) superhump period during ve nights of the superoutburst. Furthermore, we found the only possible outburst during the subsequent 100 nights.
Gravitational Interaction in the Chimney Lattice Universe †
(2021) Eingorn, Maxim; McLaughlin II, Andrew; Canay, Ezgi; Brilenkov, Maksym; Zhuk, Oleksandr I.; Жук, Олександр Іванович; Жук, Александр Иванович
We investigate the influence of the chimney topology T T R of the Universe on the gravitational potential and force that are generated by point-like massive bodies. We obtain three distinct expressions for the solutions. One follows from Fourier expansion of delta functions into series using periodicity in two toroidal dimensions. The second one is the summation of solutions of the Helmholtz equation, for a source mass and its infinitely many images, which are in the form of Yukawa potentials. The third alternative solution for the potential is formulated via the Ewald sums method applied to Yukawa-type potentials. We show that, for the present Universe, the formulas involving plain summation of Yukawa potentials are preferable for computational purposes, as they require a smaller number of terms in the series to reach adequate precision.
Groups of meteorites and meteorite-dropping fireballs in asteroidal orbits
(2021) Gorbanev, Yuriy M.; Konovalova, N. A.; Davruqov, N. Kh.; Горбаньов, Юрій Михайлович; Горбанёв, Юрий Михайлович
This paper presents the results of a study of the existence of nine near-Earth meteorite-producing groups in asteroidal orbits, containing sporadic reballs from the IAU MDC-2007 database, sporadic meteors from the SonotaCo database, meteorites namely, L5, L6 and H4−H6 ordinary chondrites and an ureilite, for which atmospheric and orbital parameters are known from instrumental observations. Orbits of the selected members of meteorite-producing groups were classi ed as asteroid orbits according to the Tisserand parameter Tj > 3.1. Dynamic links between the members of the identi ed meteorite-producing groups and instrumentally observed known meteorites which were taken as a reference for the search of potential group members were tested using orbital similarity criteria, in particular the Drummond criterion DD and the Southworth and Hawkins criterion DSH. As a result, several meteorite-dropping sporadic reballs and small meteors, whose orbits are similar to the asteroid orbits of nine known meteorites, were detected and reckoned as possible members of meteorite-producing groups.
Implementation of gravitational potential screening on large scales in an N-body code
(2019) Baldi, Marco; Burgazli, Alvina; Eingorn, Maxim; Жук, Олександр Іванович; Жук, Александр Иванович; Zhuk, Oleksandr I.
There was considered the Universe filled with cold dark matter in the form of discrete inhomogeneities (e.g., galax-ies) and dark energy in the form of arbitrary continuous per-fect fluids. The background space-time geometry is defined by the Friedmann metric.
MASTER OT J172758.09+380021.5: a peculiar ER UMa-type dwarf nova, probably a missed nova in the recent past
(2021) Pavlenko, E.; Kato, T.; Antonyuk, K.; Pit, N.; Keir, L.; Udovichenko, Serhii M.; Dubovsky, P.; Sosnovskij, A.; Antonyuk, O.; Shimansky, V.; Gabdeev, M.; Rakhmatullaeva, F.; Kokhirova, G.; Belan, S.; Simon, A.; Baklanov, A.; Kojiguchi, N.; Godunova, V.; Удовіченко, Сергій Миколайович; Удовиченко, Сергей Николаевич
A CCD photometry of the dwarf nova MASTER OT J172758.09 +380021.5 was carried out in 2019 during 134 nights. Observations covered three superoutbursts, ve normal outbursts and quiescence between them. The available ASASSN and ZTF data for 2014 { 2020 were also examined. Spectral observations were done in 2020 when the object was in quiescence. Spectra and photometry revealed that the star is an H-rich active ER UMa-type dwarf nova with a highly variable supercycle (time interval between two successive superoutbursts) of 50 { 100 d that implies a high and variable mass-transfer rate. MASTER OT J172758.09+380021.5 demonstrated peculiar behaviour: short-lasted superoutbursts (a week); a slow superoutburst decline and cases of rebrightenings; low frequency (from none to a few) of the normal outbursts during the supercycle. In 2019 a mean period of positive superhumps was found to be 0.05829 d during the superoutbursts. Late superhumps with a mean period of 0.057915 d which lasted about 20 d after the end of superoutburst and were replaced by an orbital period of 0.057026 d or its orbital-negative superhump beat period were detected. An absence of eclipse in the orbital light curve and its moderate amplitude are consistent with the orbital inclination of about 40 found from spectroscopy. The blue peaks of the V-Ic and B-Rc colour indices of superhumps during the superoutburst coincided with minima of the light curves, while B-Rc of the late superhumps coincided with a rising branch of the light curves. We found that a low mass ratio q = 0:08 could explain most of the peculiarities of MASTER OT J172758.09+380021.5. The mass-transfer rate should be accordingly higher than what is expected from gravitational radiation only, this assumes the object is in a post-nova state and underwent a nova eruption relatively recently { hundreds of years ago. This object would provide probably the rst observational evidence that a nova eruption can occur even in CVs near the period minimum.
Methods and Statistics of TV Observations of Telescopic Meteors
(Pleiades Publishing, Inc., 2006) Gorbanev, Yuriy M.; Golubaev, Aleksandr V.; Zhukov, V. V.; Knyaz’kova, Еlena F.; Kimakovskiy, Sergey R.; Kimakovskaya, Irina I.; Podlesnyak, S. V.; Sarest, Leonid A.; Stogneeva, Irina A.; Shestopalov, Vasiliy A.
A review of TV and telescopic methods of meteor observations and of the problems of meteor astronomy addressed using these methods is presented. A meteor patrol developed at the Astronomical Observatory of Odessa National University and based on a Schmidt telescope and a TV detector is described. The meteor patrol allows meteor events to be recorded with a time resolution of 0.04 s. The investigated characteristics of the patrol are reported, and some aspects of the methods of observations and reduction employed are considered. The results of observations made during the period 2003–2004 are reported. A total of 368 meteors were recorded on 1093 individual frames during a total patrol time of 679 hours within a 36′×48′ field of view. The statistical data for meteor observations are reported, and classification of meteor images is presented. The specific features of some recorded meteor events are analyzed.
Monitoring of space objects using Odessa Observatory network of telescope
(2019) Andrievsky, Serhii M.; Bazyey, N. V.; Zhukov, V. V.; Koshkin, Nikolay I.; Kashuba, V. I.; Kashuba, S. V.; Gorbanev, Yuriy M.; Sukhov, P. P.; Podlesnyak, S. V.; Udovichenko, S. N.; Keir, L. E.; Андрієвський, Сергій Михайлович; Андриевский, Сергей Михайлович; Кошкін, Микола Іванович; Кошкин, Николай Иванович; Горбаньов, Юрій Михайлович; Горбанёв, Юрий Михайлович
In this paper we are presenting optical telescopes of Astronomical Observatory of I. I. Mechnikov Odessa National University. We are describing technical characteristics and scientific program for each telescope. Here we also present a description of the tools with which the unique collections of astroplates were obtained under the program “The Sky Service”. Odessa Observatory (46°.28 N, 30°.45 E, altitude 64 m, observation code 086) it has several observational stations. Among them: Mayaki (46.39° N, 30°.27 E, altitude 25 m, observation code 583) and Kryzhanovka (46°.37 N, 30°.48 E, altitude 40 m, observation code A85). Both stations have a good geographical location, as well as good astroclimate (up to 200 clear nights or part of the night). Telescopes are equipped with modern CCDs and photometric light detectors. Odessa Observatory has its own mechanical and optical workshops that are used for construction the new telescopes and manufacture and repair other astronomical equipment.
Morphology subtypes in rich galaxy cluster with intermediate concentration
(2019) Zabolotnii, Viktor; Panko, Olena O.; Панько, Елена Алексеевна; Панько, Олена Олексіївна; Korshunov, Valerii; Yemelianov, Yaroslav
The Universe consists of many galaxy clusters which we observe on the sky. Galaxy cluster is structure that consists of many galaxies (from 10 to 1000). In our work we are looking for rich clusters (100 and more galaxies) with intermediate concentration. We used Panko classification of galaxy clusters.
Nanocomposite elements for HIC and sensors with a fusible glass matrix
(2018) Lepikh, Yaroslav I.; Lavrenova, T. I.
Functional basis of materials (pastes) for thick-film elements of hybrid integrated circuits and sensors are, as a rule, metal-oxide compounds of ruthenium, silver, palladium and gold and also oxides, carbides, boruides, nitrides, silicides of the other metals. Nanocomposite elements based on the "glass - metal compounds" are formed by the annealing of the pastes which are composed of a mix of superfine powders of a glass and a functional material which disperse in special organic binding agent.
On the annual occurrence of large and small sporadic meteoroids and meteorites
(2019) Konovalova, N. A.; Gorbanev, Yuriy M.; Davruqov, N. Kh.; Горбаньов, Юрій Михайлович; Горбанёв, Юрий Михайлович
The observations of the meteors and bright fireballs by meteor stations and fireball networks allows to get the more precise data on atmospheric trajectories and heliocentric orbits of this bodies. In recent years, several works were published on the subjects of the annual occurrence of fireballs. On the base of the Millman Fireball Archive the time of occurrence data for 2373 fireball events observed from across Canada was studied Beech [1]. An analysis of the frequency of the superfireballs based on the reports which appeared in newspapers in the last 150 years was made in [2]. Shrbeny et al. [3] studied the fireball activity from the Desert Fireball Network records from 2006 to 2014 and identified several time periods with increased number of fireballs. We present here the results of the analysis of annual occurrence of large and small sporadic meteoroids and meteorites with known fall data.
Paramètres stellaires fondamentaux et l’investigation de la Galaxie
(2019) Mishenina, Tamara V.; Мішеніна, Тамара Василівна; Мишенина, Тамара Васильевна
Il s'agit de la coopération Ukraine (Odessa) - France (Bordeaux) dans le domaine de l'astrophysique, ses origines et résultats. L'abondance de tout élément chimique, de l'hydrogène à l'uranium, etc., nous permet de tester et d'améliorer les théories cosmologiques, la théorie de la nucléosynthèse et l'évolution des étoiles, ainsi que la théorie de la formation et de l'enrichissement en éléments chimiques des galaxies. C'est ainsi qu'en 2000, mon équipe et moi avions prévu d'étudier les problèmes liés à l'enrichissement de notre Galaxie en éléments, issus de la capture de neutrons. Pour ce faire, il nous fallait des spectres d'étoiles dans une large gamme de métallicité et de bonne qualité. Nous avons trouvé de spectres requis d'étoiles dans les archives spectrales du télescope de 1,93 m et du spectrographe ELODIE de l'Observatoire de Haute Provence (France). Les spectres étaient librement disponibles, nous en avons profité et ensuite nous avons publié l'article dans la revue européenne «Astronomy and Astrophysics». Mais avan, j'ai écrit une lettre à Caroline Soubiran. Caroline Soubiran est l'une des observateurs et compilateurs des programmes d'archivage et de traitement du spectre de l’ELODIE, un expert dans la domain de la cinématique et de la dynamique de la Galaxie. En 2002, elle m’a invité à l’Observatoire de Bordeaux ( l'OASU -Observatoire Aquitain des Sciences de l‘Univers). Cela etait le debut. Puis, en 2003, il y a eu mon voyage d'affaires à l’Université de Strasbourg et mon collègue Valery Kovtyukh a visité Bordeaux. En 2005-2006, nous avons obtenu une subvention destinée à la recherche dans le cadre du programme " Dnipro" de la coopération franco-ukrainienne qui s’appele «Paramètres stellaires fondamentaux et l’investigation de la Galaxie». Caroline Soubiran a visité l’Université d’Odessa et notre observatoire en 2005-2006. Notre coopération se poursuit à l'heure actuelle.

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