Formation histories of galactic halos via chemical abundance analyses of near-by stellar systems

• Applicant: Dr. Andreas Koch-Hansen, Ph.D.
• Subject Area: Astrophysics and Astronomy
• Term: from 2011 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 193251414

I propose to establish a research group to investigate the formation of nearby galaxies, with a particular focus on the halos of our Milky Way galaxy and its nearest neighbour, the M31 galaxy. The aim is to measure chemical element abundances of stars in near-by dwarf galaxies and in globular clusters using high-resolution spectroscopy obtained with instruments at the ESO/VLT, LBT, Magellan, and Keck telescopes, and additional existing and archival data. These data will be analyzed using state-of-the-art techniques. By comparing the properties of the lowest-mass dwarf galaxies with star clusters in the outskirts of the Milky Way and with stars of the Galactic halo, it can be estimated to what extent such systems can be considered as building blocks of our Milky Way. Furthermore, it is believed that the dwarf galaxies are the sites of the earliest star formation in the Universe, which can be tagged via the chemical characteristics of their metal poor stars. Finally, narrowband photometry in the M31 halo will allow one to identify the predominant stellar populations in the outer regions and in substructures of this galaxy. From this, M31’s formation history can be efficiently reconstructed.

• DFG Programme: Independent Junior Research Groups