Counter-Rotating Disks in Galaxies

Counter-rotation is a phenomenon found in some galaxies; it happens when a counter-rotating disk which rotates in an opposite direction to the main disk is found. There have been many suggestions explaining the evolution of galaxies with this feature. Mainly, it has been theorized that an accretion of gas or stars due to merging or acquiring material from another galaxy can lead to the formation of a counter-rotating disk. By studying the kinematics of the stars within a galaxy, we can try to detect this phenomenon. Further investigation of the properties of the stars can support our understanding of the history of the formation of both disks. In this thesis, we aim to look for counter-rotation in some lenticular and spiral galaxies. Moreover, we will select some galaxies and look at their stellar properties to try to suggest the evolutionary history of its components.