• Periodic variability in active galactic nuclei 

      Kudryavtseva, Nadezhda (Univ. Köln, 2008)
      In this doctoral thesis, multi-frequency very long baseline interferometry observations together with multi-frequency total flux-density variability data of compact relativistic jets in active galactic nuclei are presented ...
    • Search for tidal streams in disk and halo 

      Schmithüsen, Olaf (Univ. Bochum, 2008)
      This work deals with the search for substructures in four nearby galaxies (NGC 300, NGC 7793, M 33, M 83) in which it is possible to resolve single stars in their outer parts.The search is based on the photometry of wide ...
    • Stability of flat galaxies 

      Fiřt, Roman (2008)
      In this thesis we investigate the existence and properties of stationary solutions of the flat Vlasov-Poisson system. This system of partial differential equations can be used as a model of extremely flat astronomical ...
    • The vertical structure of thickened bars in disk galaxies 

      Aronica, Giuseppe Agostino (Univ. Bochum, 2006)
      In der vorliegenden Dissertation wird die vertikale Struktur von edge-on Scheibengalaxien mit einer 'box or peanut shaped' (B/PS) Struktur in der Bulgeregion unter Verwendung von nahinfrarot Beobachtungen untersucht. Durch ...