“…Several aspects of galactic orientations within separate clusters were investigated in a few ways. There seems to exist compelling evidence for strong alignment of a cD galaxy with its cluster, and the effect is stronger in more elongated clusters (Struble 1987(Struble , 1990Mandzhos 1987;van Kampen & Rhee 1990;Trevese, Cirimele & Flin 1992;Han, Gould & Sackett 1995). Muriel & Lambas (1992) showed the existence of systematic effects in orientations of galaxies with respect to their neighbours.…”
A B S T R A C TWe investigate the orientations of the galactic axes within 18 selected clusters, substructures of the Local Supercluster. For every cluster we map the parameter D 11 describing the alignment of the galactic axes with respect to a chosen cluster pole, divided by its formal error jðD 11 Þ [s ϵ D 11 =jðD 11 Þ]. The cluster pole coordinates change along the entire celestial sphere. The resulting maps are analysed for correlations of their maxima with directions from the cluster centre to (i) the derived 'physical' cluster poles, (ii) the Local Supercluster centre, (iii) the Virgo A centre and (iv) the Earth, i.e. along the line of sight (ϵ LOS). The strong maximawith one exception -exist only for non-spiral (NS) subsamples, with the maximum well correlated with the LOS direction. Another of the studied directions may occur close to the maximum only if these directions are close to the LOS and they do not correlate with other features visible on the maps. For clusters with a clearly defined maximum of s below 3:0 the conclusion generally does not change. For the spiral (S) subsamples the maps are usually at the random noise level. In these cases a weaker, but still existing correlation with the LOS is observed and no other evident correlations are noted. We conclude that a strong systematic effect, generated by the process of deprojection of a galactic axis from its optical image, is present in the catalogue data. It can mask any weak alignment existing in the analysed clusters. With the use of a simple model for the systematic effect we are able to reproduce the main characteristic features of the maps for non-spiral galaxies. We note, however, that a few clusters show significant differences with respect to this model.
“…Several aspects of galactic orientations within separate clusters were investigated in a few ways. There seems to exist compelling evidence for strong alignment of a cD galaxy with its cluster, and the effect is stronger in more elongated clusters (Struble 1987(Struble , 1990Mandzhos 1987;van Kampen & Rhee 1990;Trevese, Cirimele & Flin 1992;Han, Gould & Sackett 1995). Muriel & Lambas (1992) showed the existence of systematic effects in orientations of galaxies with respect to their neighbours.…”
A B S T R A C TWe investigate the orientations of the galactic axes within 18 selected clusters, substructures of the Local Supercluster. For every cluster we map the parameter D 11 describing the alignment of the galactic axes with respect to a chosen cluster pole, divided by its formal error jðD 11 Þ [s ϵ D 11 =jðD 11 Þ]. The cluster pole coordinates change along the entire celestial sphere. The resulting maps are analysed for correlations of their maxima with directions from the cluster centre to (i) the derived 'physical' cluster poles, (ii) the Local Supercluster centre, (iii) the Virgo A centre and (iv) the Earth, i.e. along the line of sight (ϵ LOS). The strong maximawith one exception -exist only for non-spiral (NS) subsamples, with the maximum well correlated with the LOS direction. Another of the studied directions may occur close to the maximum only if these directions are close to the LOS and they do not correlate with other features visible on the maps. For clusters with a clearly defined maximum of s below 3:0 the conclusion generally does not change. For the spiral (S) subsamples the maps are usually at the random noise level. In these cases a weaker, but still existing correlation with the LOS is observed and no other evident correlations are noted. We conclude that a strong systematic effect, generated by the process of deprojection of a galactic axis from its optical image, is present in the catalogue data. It can mask any weak alignment existing in the analysed clusters. With the use of a simple model for the systematic effect we are able to reproduce the main characteristic features of the maps for non-spiral galaxies. We note, however, that a few clusters show significant differences with respect to this model.
“…[29]. It also should be noticed that Mandzhos et al [31,32], during the analysis of UGC [10] (north hemisphere) and ESO [11] (south hemisphere) galaxies, found that galaxies major axes are distributed anisotropically.…”
In 1994 Parnovsky, Karachentsev and Karachentseva suggested a modified method for the investigation of the orientations of galaxies. Using this method they analyzed galaxies from the UGC and ESO catalogues, as well as from their own catalogue inclusive of flat edge-on galaxies. They found statistically significant anisotropy in the galaxies orientations. In 1995 Flin suggested that this anisotropy has to be specific to Local Supercluster (LSC). In the present paper, using the method proposed by Parnovsky, Karachentsev and Karachentseva in 1994, we analyzed the orientation of galaxies in the sample of galaxies belonging to LSC founding a weak anisotropy only. The relation of this method to Hawley and Peebles (1975) method of the investigation of the orientation of galaxies was discussed as well.
“…The third, shortest, axis (0.778) points towards the Celestial Pole. Mandzhos et al [6], too, analyzed the orientation of UGC and ESO galaxies and showed that the cylindrical model of spatial orientation agrees best with observations. The axis of the cylinder, perpendicularly to the lateral surface of which the galactic normals are preferentially oriented, points towards the Celestial Pole.…”
An analysis of the position angles distribution of 10461 extended radio sources shows that the spatial orientation of the axes of these objects is anisotropic: they avoid the direction towards the Celestial Pole and are mostly oriented in the equatorial direction. The ratio of the probability densities of the orientation in these two directions is 0.68. The probability that the sky distribution of axes is isotropic is less than 0.00004. This conclusion is consistent with the results of the analyses of spatial distribution of galactic normals orientation in the galaxies from the UGC, ESO, and FGC catalogs.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.