The Rotational Centre of the Large Magellanic Cloud

Sammanfattning: The Large and Small Magellanic Clouds (LMC & SMC) are the two largest galaxies orbiting the Milky Way (MW). The interactions between them have affected the evolution of both galaxies. The interactions have affected the galaxies differently depending on how strong they have been. Tidal forces from the interactions are argued to have produced a stream of stars and gas called the Magellanic Bridge. Due to the population of stars being young in the Bridge it is concluded that the Bridge was formed of only gas which was stripped from the galaxies. The Bridge is one of the most prominent proof that there have been a few or several interactions between the Small and Large Magellanic Cloud. In this thesis, we have looked at eight evolutionary phases of stars with different ages for the different phases. They cover a wide range of ages from very young to old stars. We looked at how their proper motion, rotational velocity, and rotational centres behave and what differences and similarities we can see between the stellar populations. This was done using three different models for the rotational and radial velocities where one of the models was used with masked and unmasked data. The rotation curve for each of the populations was derived as well as the internal velocities, the velocities within the LMC. By fitting a model with a non-fixed centre we could determine the rotational centres for the stellar populations. These centres were compared to results of other authors. We find that the centres derived in this thesis are closer together than what was previously derived. We can therefore conclude that the interactions have affected the LMC less than what was previously theorised.