Search for dissertations about: "galactic evolution"

Showing result 21 - 25 of 48 swedish dissertations containing the words galactic evolution.

  2. 21. Observational Studies of the Chemical Evolution in the Galactic Thin and Thick Disks

    Author : Thomas Bensby; Astronomi - Genomgår omorganisation; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Astronomy; Astronomi; Fysicumarkivet A:2004:Bensby;

    Abstract : The origin and evolution of the thin and thick disks in the Galaxy have been studied by means of detailed stellar abundances. High-resolution spectra of 102 F and G dwarf stars have been obtained with the spectrographs on the ESO 3.6-m and ESO 1. READ MORE

  4. 22. High-redshift active galactic nuclei and their environment

    Author : Judit Fogasy; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; galaxies: evolution -- galaxies: high-redshift -- galaxies: active -- galaxies: Starburst -- -- Submillimeter: galaxies;

    Abstract : In order to understand the formation and evolution of local massive galaxies and to reveal the processes that engineered the tight correlations found between their supermassive black hole (SMBH) mass and bulge mass or velocity dispersion, the study of powerful, high-redshift active galactic nuclei (AGNs) and their environment is crucial. AGNs are luminous targets providing important clues to galaxy evolution, as their central SMBH is growing at high rates, which opens the opportunity to unfold how the growth of the black hole influences the growth of its host galaxy. READ MORE

  5. 23. Star clusters as engines of galaxy evolution

    Author : Mattia Sirressi; Angela Adamo; Matthew Hayes; Paul Crowther; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Extragalactic astronomy; Galaxies; Star formation; Interstellar medium; Stellar feedback; Ultraviolet surveys; Hubble Space Telescope; Spectroscopy; Data analysis; Astronomy; astronomi;

    Abstract : Feedback in star forming galaxies is the key process that regulates how many stars form given the available gas reservoir. The radiation, energy and momentum released by the stellar activity and the active galactic nuclei change the physical properties of the gas in the galaxy such as the ionisation state, the density and the kinematics. READ MORE

  6. 24. Star clusters as engines of galaxy evolution

    Author : Mattia Sirressi; Angela Adamo; Matthew J. Hayes; Johan Fynbo; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : Stars form and live in hierarchical structures such as star clusters on the smallest scales up to groups of galaxies on the largest scales. The role of young and massive star clusters in the evolution of the host galaxies is one of the most active fields of research in modern astronomy. READ MORE

  7. 25. On the Chemical Composition of Metal-Poor Stars : Impact of Stellar Granulation and Departures from Local Thermodynamic Equilibrium on the Formation of Spectral Lines

    Author : Remo Collet; Bengt Gustafsson; Martin Asplund; Roger Cayrel; Uppsala universitet; []
    Keywords : Astronomy; late-type stars; stellar abundances; stellar atmospheres; spectral line formation; convection; hydrodynamics; Galactic chemical evolution; Astronomi;

    Abstract : The information about the chemical compositions of stars is encoded in their spectra. Accurate determinations of these compositions are crucial for our understanding of stellar nucleosynthesis and Galactic chemical evolution. READ MORE