Some aspects of the orientation of galaxies in clusters

TL;DR

This paper investigates the spatial orientation of galaxies in Tully's groups within the Local Supercluster, analyzing how galaxy morphology affects alignment and discussing implications for galaxy formation theories.

Contribution

It introduces an improved method for analyzing galaxy alignment and examines the dependence of orientation on galaxy morphological types.

Findings

No significant deviations from isotropy in galaxy orientations.

Orientation dependence varies with galaxy morphological type.

Implications for galaxy formation theories are discussed.

Abstract

The analysis of Tully's groups of galaxies belonging to the Local Supercluster (LSC) was performed. In the 1975 Hawley and Peebles presented the method for investigations of the galaxies orientation in the large structures. In our previous papers statistical test proposed by Hawley and Peebles for investigation of this problem was analyzed in details and some improvements were suggested. On this base the new method of the analysis of galactic alignment in clusters was proposed. Using this method, God{\l}owski (2012) analyzed the orientation of galaxies inside Tully's group founding no significant deviations from isotropy both in orientation of position angles and $\delta_D$ and $\eta$ angles as well, giving the spatial orientation of galaxy planes. In the present paper we examined carefully and methodically the dependence of alignment in Tully's groups on morphological type of galaxies. Moreover, we discussed the consequences of different approximation of "true shape" of the galaxies for different morphological types, possible influence of this problem for investigation of spatial orientation of galaxies. In addition, we discussed the implications of the obtained results for the theory of galaxy formation as well.