eprintid: 25607 rev_number: 16 eprint_status: archive userid: 4095 dir: disk0/00/02/56/07 datestamp: 2018-11-14 05:58:48 lastmod: 2019-01-11 08:30:17 status_changed: 2018-11-14 05:58:48 type: doctoralThesis metadata_visibility: show creators_name: Buck, Tobias title: On the formation of the Milky Way system in cosmological context - A numerical study subjects: 500 subjects: 520 subjects: 530 divisions: 130001 adv_faculty: af-13 abstract: State-of-the-art cosmological hydrodynamical simulations have succeeded in modelling realistic Milky Way (MW) type galaxies with spatial resolution of the order of a few hundred parsec, similar to the scale-height of MW's stellar disc and the half-light radius of classical satellite galaxies. I divide the present study into two parts, the build-up of MW's stellar disc and bulge and the formation and evolution of its satellites and dwarf galaxies. In the first part I show that observed clumpy stellar discs in the early phases of the formation of the Galaxy are dynamically unimportant for its further evolution. This confirms recent observational results where a non linear mapping between stellar mass and light causes stellar discs to appear clumpy. I turn then to explore the formation mechanism of a peanut bulge in cosmological context. I study the kinematical properties of the central stellar populations of a model galaxy using a kinematical decomposition technique and find that the observed kinematic features of the (MW) bulge can only be explained if it consists of both, a peanut bulge and a spherically symmetric bulge both formed via disc instabilities. Observing and disentangling both components will soon be possible thanks to large scale Galactic surveys like Gaia. In the second part I study the dwarf galaxy population of (MW) mass galaxies. The simulations presented here are among the first to be able to study the formation of dwarf satellite galaxies in a realistic cosmological environment. The employed sub-grid models of the simulations reconcile simulated and observed Local Group satellite mass functions and produce dwarf galaxies whose central stellar velocity dispersion agrees with observations. Using the dwarf galaxies, I test the observational prospects of identifying tidally affected dwarfs in the Local Group using three observables: their distance, line-of-sight velocity and central velocity dispersion. Finally, I investigate the evolution of planes-of-satellites in the framework of the Cold Dark Matter model with a cosmological constant (ΛCDM). These planes quickly dissolve because they consist of a large fraction of chance aligned satellites as recently confirmed with the proper motions of the classical satellite galaxies derived from Gaia data. date: 2018 id_scheme: DOI id_number: 10.11588/heidok.00025607 ppn_swb: 1653325208 own_urn: urn:nbn:de:bsz:16-heidok-256072 date_accepted: 2018-10-19 advisor: HASH(0x556120944290) language: eng bibsort: BUCKTOBIASONTHEFORMA2018 full_text_status: public citation: Buck, Tobias (2018) On the formation of the Milky Way system in cosmological context - A numerical study. [Dissertation] document_url: https://archiv.ub.uni-heidelberg.de/volltextserver/25607/1/phd_thesis_buck.pdf