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Документ A catalogue of galaxy clusters and groups as base for new galaxy supercluster catalogue(Odessa I.I. Mechnikov National University, 2009) Panko, Olena O.; Панько, Олена Олексіївна; Панько, Елена АлексеевнаДокумент Alignment of galaxies in subclustres placed in rich regions(2019) Korshunov, V.; Panko, Olena O.; Панько, Елена Алексеевна; Панько, Олена ОлексіївнаThe 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).Документ Detailed morphology of the rich concentrated Galaxy Clusters(Одеський національний університет імені І. І. Мечникова, 2018) Panko, Olena O.; Sirginava, A.; Stepaniuk, A.; Панько, Елена Алексеевна; Сиргинава, А.; Степанюк, А.; Панько, Олена ОлексіївнаThe results of the detailed analysis of the 2D distribution of galaxies in 28 rich galaxy clusters with significant concentration to the cluster center are present. The analysis was executed in these directions: the detection of regular substructures and peculiarities in the galaxy distribution. The role of brightest cluster members was taken into account too. The input data were selected from “The Catalogue of Galaxy Clusters and Groups” and list of galaxies of Muenster Red Sky Survey. Concentrated galaxy clusters are evolved, virialized structures. Substructures in this type of clusters must be feeble marked. Nevertheless we detected significant part of concentrated galaxy clusters having different kinds of peculiarities, namely crossing and divaricating filaments or X and Y-type peculiarities, as well as curved strips and short dense chains. 2 clusters having extremely density of galaxies were attributed as superconcentrated/compact type.Документ Galaxy Cluster Mergers: the use of the computer modeling(Одеський національний університет імені І. І. Мечникова, 2023) Berkovskyi, M.; Panko, Olena O.; Miroshnik, N.; Панько, Олена ОлексіївнаWe show the possibilities of the methods of computer modeling of the galaxy cluster merger process with different initial parameters for the investigation of the features of the clusters after colliding. Weconsideredthegalaxyclustersasevolvingobjects including through collisions. Computer modeling of galaxy cluster mergers and comparing its results with observational data makes it possible to determine the evolutionary status of real clusters with complex internal structures. Within the study, we analyzed in detail a series of models of the galaxy clusters’ merger consequences by ZuHone under different initial conditions like mass ratio, initial collision parameter, or plasma coefficient β. The considered time intervals were from 0 to 4.8 billion years, from 0 to 6 billion years, and from 0 to 10 billion years, depending on the initial conditions. Basedontheimagesofthesimulatedgalaxyclusters, maps of the distribution of the total mass density and X-ray radiation were created and compared with observations. We showed a good perspective to use this catalog for studying galaxy clusters having compound inner structure.Документ Investigation of the orientation of galaxies in clusters: the importance, methods and results of research(2019) Pajowska, Paulina; Godlowski, Wlodzimierz; Zhu, Zong-Hong; Popiela, Joanna; Panko, Olena O.; Flin, Piotr; Панько, Олена Олексіївна; Панько, Елена АлексеевнаVarious models of structure formation can account for various aspects of the galaxy formation process on different scales, as well as for various observational features of structures. Thus, the investigation of galaxies orientation constitute a standard test of galaxies formation scenarios since observed variations in angular momentum represent fundamental constraints for any model of galaxy formation. We have improved the method of analysis of the alignment of galaxies in clusters. Now, the method allows to analyze both position angles of galaxy major axes and two angles describing the spatial orientation of galaxies. The distributions of analyzed angles were tested for isotropy by applying different statistical tests. For sample of analyzed clusters we have computed the mean values of analyzed statistics, checking whether they are the same as expected ones in the case of random distribution of analyzed angles. The detailed discussion of this method has been performed. We have shown how to proceed in many particular cases in order to improve the statistical reasoning when analyzing the distribution of the angles in the observational data. Separately, we have compared these new results with those obtained from numerical simulations. We show how powerful is our method on the example of galaxy orientation analysis in 247 Abell rich galaxy clusters. We have found that the orientations of galaxies in analyzed clusters are not random. It means that we genuinely confirmed an existence of the alignment of galaxies in rich Abells’ galaxy clusters. This result is independent from the clusters of Bautz-Morgan types.Документ Isolated clusters of PF catalogue(Astroprint, 2012) Panko, Olena O.; Andrievsky, Serhii M.; Андрієвський, Сергій Михайлович; Андриевский, Сергей Михайлович; Панько, Елена Алексеевна; Панько, Олена ОлексіївнаThe properties of isolated galaxy clusters are discussed. The clusters were found among 1746 PF clusters inclusive 50 and more galaxies in structure field. For 19 clusters with distances to the nearest neighbour larger than 68.5 h-1 Mpc we assigned the morphological types of these clusters according to Abell and Bauts & Morgan. The existence of preferential planes and angular momenta of isolated clusters was assumed. We connect evolution of isolated clusters with common large-scale characteristics.Документ Linear substructures in Galaxy clusters(Одеський національний університет імені І. І. Мечникова, 2019) Panko, Olena O.; Korshunov, V.; Yemelianov, S.; Zabolotnii, V.; Панько, Олена Олексіївна; Панько, Елена АлексеевнаWe propose detailed scheme that is describing the morphology of linear substructures in galaxy clusters. Our base morphological scheme divides galaxy clusters using numerical criteria according the parameters: concentration to the cluster center, the presence of linear substructure, orientation of images of galaxies, the role of brightest cluster members, the shape of galaxies. Our analysis of 2D distribution of galaxies based on study more than 500 galaxy clusters. We show the linear substructures are regular peculiarity in galaxy clusters. Our approach allows to divide filamentary and edge-on wall substructures and to select galaxy clusters with possible peculiarities in hot gas and/or DM distribution.Документ Morphological types of 254 Rich PF Galaxy Clusters(Astroprint, 2014) Panko, Olena O.; Andrievskii, Alexander M.; Gotsulyak, A. V.; Андрієвський, Олександр Михайлович; Панько, Елена Алексеевна; Панько, Олена Олексіївна; Андриевский, Александр МихайловичWe determined the morphological types for 254 rich galaxy clusters from the PF Catalogue of Galaxy Clusters and Groups. The data get contains the PF galaxy clusters, which have no ACO coinciding ones. The applied morphological scheme was combined of the prevalent classifications, such as Bautz-Morgan, Rood-Sastry etc approaches. We assigned the morphological types using numerical criteria and taking into consideration concentration to the cluster center, the signs of preferential direction or plane in the cluster, and the positions of the brightest galaxies. The features of the data set are discussed.Документ Morphology subtypes in rich galaxy cluster with intermediate concentration(2019) Zabolotnii, Viktor; Panko, Olena O.; Панько, Елена Алексеевна; Панько, Олена Олексіївна; Korshunov, Valerii; Yemelianov, YaroslavThe 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.Документ On the existence of young embedded clusters at high Galactic latitude(2017) Turner, D. G.; Carraro, G.; Panko, Olena O.; Панько, Олена Олексіївна; Панько, Елена АлексеевнаCareful analyses of photometric and star count data available for the nine putative young clusters identified by Camargo et al. (2015, 2016) at high Galactic latitudes reveal that none of the groups contain early-type stars, and most are not significant density enhancements above field level. 2MASS colours for stars in the groups match those of unreddened late-type dwarfs and giants, as expected for contamination by (mostly) thin disk objects. A simulation of one such field using only typical high latitude foreground stars yields a colour-magnitude diagram that is very similar to those constructed by Camargo et al. (2015, 2016) as evidence for their young groups as well as the means of deriving their reddenings and distances. Although some of the fields are coincident with clusters of galaxies, one must conclude that there is no evidence that the putative clusters are extremely young stellar groups.Документ Orientation of Brighter Galaxies in Nearby Galaxy Clusters(2009) Panko, Olena O.; Juszczyk, T.; Flin, P.; Панько, Олена Олексіївна; Панько, Елена АлексеевнаA sample of 6188 nearby galaxy structures, complete to rF = 18. m 3 and containing at least 10 members each, was the observational basis for an investigation of the alignment of bright galaxies with the major axes for the parent clusters. The distribution of position angles for galaxies within the clusters, specifically the brightest, the second brightest, the third, and the tenth brightest galaxies was tested for isotropy. Galaxy position angles appear to be distributed isotropically, as are the distributions of underlying cluster structure position angles. The characterization of galaxy structures according to richness class also appears to be isotropic. Characterization according to BM types, which are known for 1056 clusters, is more interesting. Only in the case of clusters of BM type I is there an alignment of the brightest cluster member with the major axis of the parent cluster. The effect is observed at the 2 significance level. In other investigated cases the distributions are isotropic. The results confirm the special role of cD galaxies in the origin/evolution of large-scale structures.Документ The Adopted Morphological Types of 247 Rich PF Galaxy Clusters(2016) Panko, Olena O.; Bajan, Katarzyna; Flin, Piotr; Gotsulyak, Alla; Панько, Олена Олексіївна; Панько, Елена АлексеевнаMorphological types were determined for 247 rich galaxy clusters from the PF Catalogue of Galaxy Clusters and Groups. The adopted types are based on classical morphological schemes and consider concentration to the cluster center, the signs of preferential direction or plane in the cluster, and the positions of the brightest galaxies. It is shown that both concentration and preferential plane are significant and independent morphological criteria.Документ THE CRITERIA FOR MORPHOLOGICAL CLASSIFICATION OF PF GALAXY CLUSTERS(Astroprint, 2013) Panko, Olena O.; Панько, Елена Алексеевна; Панько, Олена ОлексіївнаThe morphological types of galaxy clusters resulting from their outward appearance is physically related to the clusters and their member galaxies. Presented here is an adopted system of morphological types of galaxy clusters based on the Zwicky, Boutz & Morgan, Rood & Sastry, and L´opez-Cruz systems. The adopted types are suitable for automated classification of galaxy clusters from The Catalogue of Galaxy Clusters and Groups (Panko & Flin 2006). Numerical criteria describing 6 main types were distinguished: Concentrated C, Intermediate I, Open O, Line L, Flat F, and cD. The types correspond to the base divisions from regular to irregular clusters, but also note the presence of preferential direction or plane in each cluster.Документ The Evolution of Low-Redshift Galaxy Structures(2009) Biernacka, Monika; Flin, Piotr; Panko, Olena O.; Панько, Олена Олексіївна; Панько, Елена АлексеевнаEllipticities for 6188 low-redshift (z < 0.18) poor and rich galaxy structures have been examined along with their evolution using an optical observational base that is statistically complete. The shape of each structure projected on the celestial sphere was determined using the covariance ellipse method. Analysis of the data indicates that structure ellipticity changes with redshift, being smaller for nearby objects and greater for those located further away. Such a change is also described better by quadratic or exponential relations than by a simple linear scheme. It is concluded that between redshifts of z = 0.18 and z = 0 we observe the dynamical evolution of galaxy clusters. Such a change in ellipticity with redshift is expected in ΛCDM models.Документ The Investigation of the Luminosity Function for Sample 6168 Galaxy Clusters(2018) Godlowski, Wlodzimierz; Popiela, Joanna; Biernacka, Monika; Bajan, Katarzyna; Panko, Olena O.; Pajowska, Paulina; Flin, Piotr; Панько, Олена Олексіївна; Панько, Елена АлексеевнаThe issue of construction of the luminosity function is an important problem for analysis of large scale structure statistics and interpretation of astronomical object counts In the present paper we discuss the the issure of the construction of the luminosity function for galaxy clusters. The problem is solved based on counting brightness of galaxies belonging to 6168 galaxy clusters selected from Panko & Flin (2006) Catalogue. We show that the galaxy clusters are characterized by the luminosity function signi cantly di erent than that obtained for both: individual optical galaxies and radiogalaxies. We discuss the signi cance of this result for the theories of the structure formation.Документ The Orientation of Galaxies in Galaxy Clusters(2010) Godlowski, Wlodzimierz; Pajowska, Paulina; Panko, Olena O.; Flin, Piotr; Панько, Олена Олексіївна; Панько, Елена АлексеевнаWe present an analysis of the spatial orientations of galaxies in 247 optically selected rich Abell clusters which have at least 100 members in the considered area.We investigated the relation between angles that give information about galaxy angular momenta and the number of members in each structure. The position angles of the galaxies’ major axes, as well as two angles describing the spatial orientation of the galaxy plane, were tested for isotropy by applying three different statistical tests. It is found that the values of the statistics increase with the amount of the galaxies’ members, which is equivalent to the existence of a relation between anisotropy and the number of galaxies in a cluster. The search for connection between the galaxies’ alignments and Bautz–Morgan (BM) morphological types of examined clusters showed a weak dependence. A statistically marginal relation between velocity dispersion and cluster richness was observed. In addition, it was found that the velocity dispersion decreases with BM type at almost 3σ level. These results show the dependence of alignments with respect to clusters’ richness, which can be regarded as an environmental effect.Документ The peculiarities in O-type Galaxy clusters(Одеський національний університет імені І. І. Мечникова, 2017) Panko, Olena O.; Emelyanov, S. I.; Панько, Елена Алексеевна; Панько, Олена ОлексіївнаWe present the results of analysis of 2D distribution of galaxies in galaxy cluster fields. The Catalogue of Galaxy Clusters and Groups PF (Panko & Flin) was used as input observational data set. We selected open rich PF galaxy clusters, containing 100 and more galaxies for our study. According to Panko classification scheme open galaxy clusters (O-type) have no concentration to the cluster center. The data set contains both pure O-type clusters and O-type clusters with overdence belts, namely OL and OF types. According to Rood & Sastry and Struble & Rood ideas, the open galaxy clusters are the beginning stage of cluster evolution. We found in the O-type clusters some types of statistically significant regular peculiarities, such as two crossed belts or curved strip. We suppose founded features connected with galaxy clusters evolution and the distribution of DM inside the clusters.Документ The Properties of Nearby Galaxy Structures(2009) Biernacka, Monika; Flin, Piotr; Juszczyk, T.; Panko, Olena O.; Панько, Олена Олексіївна; Панько, Елена АлексеевнаWe constructed the statistically uniform catalogue of 6188 galaxy structures, having at least 10 members in the structure field. These structures were extracted through the application of the Voronoi tessellation to Muenster Red Sky Survey which is a catalogue of galaxies based on scans of 217 ESO plates in the region covering about 5000 square degrees. We found that the shape of structures projected on the celestial sphere is different for rich and poor structures, which can reflect condition during their formation. Recent (for z < 0.18) weak dynamical evolution of galaxy clusters is observed. The distributions of position angles of ten brightest galaxies in structure are isotropic. The position angle of the brightest cluster member tend to be align with the parent cluster major axis only in the case of BM type I clusters, this is clusters containing cD galaxy.Документ The Shape of Galaxy Structures(The Astrophysical Journal, 2009) Panko, Olena O.; Juszczyk, Teresa; Biernacka, Monika; Flin, Piotr; Панько, Олена Олексіївна; Панько, Елена АлексеевнаAn analysis is presented for a statistically complete sample of 547 galaxy structures with z 0.16, each containing at least 10 objects. The sample was divided according to structure richness, representing 10 richness classes, with the distribution of ellipticities differing among individual classes. Mean ellipticity varies from 0.34 to 0.18, less well populated structures being more elongated that richer ones. Statistics indicate that structures with at least 50 members originate from the same population. The mean redshift of a structure class is a function of richness, with less well populated classes exhibiting greater mean redshifts than richer galaxy clusters. Further analysis reveals a dependence of the ellipticity-redshift correlation on structure richness. Among rich galaxy clusters there is an anticorrelation between the parameters, the strongest correlation occurring for the most poorly populated galaxy classes.Документ The Structure of Galaxy Clusters: Principal Components(2017) Panko, Olena O.; Панько, Олена Олексіївна; Панько, Елена АлексеевнаThis review summarises the properties of galaxy clusters and their components, namely cluster morphology, richness, morphological types of cluster members and their morphology-density relation, velocity dispersion and mass of clusters, intracluster gas and stars, and also Dark Matter in the clusters.