Tidal Tails of Star Clusters as Tools for Studying the Milky-Way Potential

• Applicant: Professor Dr. Pavel Kroupa
• Subject Area: Astrophysics and Astronomy
• Term: from 2010 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 170959259

An increasing number of tidal streams and stellar overdensities, some of yet unknown origin, have been discovered around the Milky Way, making a detailed understanding of these tidal features desirable as they prove to be the best tools to determine a cluster’s orbit and in this way constrain the Milky-Way potential.Building upon recent theoretical and numerical work we apply for the first time high precision N-body codes to study the formation and evolution of tidal streams from star clusters. We use a GPU-enabled NBODY6 code to investigate the formation of substructure within tidal streams and the influence of dark-matter substructure in the Galactic halo on these dynamically cold structures.The results will help to understand the lumpy appearance of the Milky-Way globular cluster Palomar 5 and its tidal tails as well as the recently discovered GD-1 stream, will improve orbit determinations of NGC5466 and NGC4147, and will give constraints on the Milky-Way potential, especially on the properties of dark-matter subhalos in the Milky Way. Therefore, our work will give an important test of our understanding of structure formation in the Universe.

• DFG Programme: Research Grants