Dissertation

Tracing the journey of the sun and the solar siblings through the Milky Way

Supervisor: S.F. Portegies Zwart Co-Supervisor: A.G.A. Brown

Author: Carmen Martinez Barbosa
Date: 13 April 2016
Links: Thesis in Leiden Repository

This thesis is focused on studying the motion of the Sun and the Solar siblings through the Galaxy. The Solar siblings are stars that were born with the Sun in the same molecular cloud 4.6 Gyr ago. In the first part of the thesis, we present an efficient method to calculate the evolution of small systems embedded in larger systems. Generalizations of this method are used to calculate the motion of the Sun and the Solar siblings in an analytical potential containing a central bar and spiral arms. By integrating the orbit of the Sun backwards in time, we determine its birth radius and the amount of radial migration experienced by our star. The birth radius of the Sun is used to investigate the evolution and disruption of the Sun's birth cluster. Depending on the Galaxy model parameters, the present-day phase-space distribution of the Solar siblings might be quite different. We used these data to predict the regions in the Galaxy where it will be more likely to search for Solar siblings in the future. Finally, we compute the stellar encounters experienced by the Sun along its orbit and their role on the stability of the outer Solar System.