Search for dissertations about: "stellar astronomy"

Showing result 1 - 5 of 134 swedish dissertations containing the words stellar astronomy.

  1. 1. On the Abundances of Li, Be and O in Metal-Poor Stars in the Galaxy

    Author : Ana Elia García Pérez; Martin Asplund; Bengt Gustafsson; Francesca Primas; Beatriz Barbuy; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Astronomy; galactic evolution; stellar abundances; stellar atmospheres; spectral line formation; stellar mixing; Astronomi; Astronomy and astrophysics; Astronomi och astrofysik;

    Abstract : Stellar atmospheres constitute excellent environments to study the chemical evolution of our Galaxy. The chemical composition of these atmospheres reflects the composition of the gas from where these stars were born. READ MORE

  2. 2. Characterising Young Stellar Binaries

    Author : Per Calissendorff; Markus Janson; Eric Stempels; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Binaries; stellar ages; multiplicity; Astronomy; astronomi;

    Abstract : Stars are dispersed all over the sky within our Galaxy, appearing in large varieties of ages and sizes. How- ever, estimating said traits proves not to always be trivial, but certain circumstances allow us to probe the characteristics of stellar binaries. READ MORE

  3. 3. Stellar Winds of Cool Giants : Investigating the Mass-Loss Mechanism of AGB Stars

    Author : Sofie Liljegren; Susanne Höfner; Kjell Eriksson; Bernd Freytag; Hans Olofsson; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; late-type stars; AGB stars; stellar winds; stellar atmospheres; dust; stellar pulsation; hydrodynamics; radiative transfer;

    Abstract : Asymptotic giant branch (AGB) stars are luminous cool giants of low to intermediate mass that are strongly pulsating and non-spherical, with heavy mass loss through a stellar wind. The mass loss makes these stars important for galactic chemistry, as the wind enriches the interstellar medium with new elements and dust, and it determines the final fate of these stars. READ MORE

  4. 4. Chemical Abundance Analysis of Population II Stars : The Summary Includes a Background in General Astronomy

    Author : Karin Jonsell; Bengt Gustafsson; Bengt Edvardsson; Paul Barklem; Christopher Sneden; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Astronomy; Astronomy; Galactic evolution; Halo; Milky Way; Oxygen; r-element; s-element; Stellar abundances; Astronomi; Astronomy and astrophysics; Astronomi och astrofysik;

    Abstract : We are made of stardust in the sense that most atomic nuclei around us have been formed by stars. Stars synthesise new elements and expel them to the interstellar medium, from which later new generations of stars are born. We can map this chemical evolution by analysing the atmospheric contents of old Galactic halo stars. READ MORE

  5. 5. Atomic Influences in Stellar Spectroscopy

    Author : Krister Nielsen; Atomfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; magnetic and optical properties; supraconductors; magnetic resonance; relaxation; Kondenserade materiens egenskaper:elektronstruktur; spectroscopy; rymdvetenskap; kosmisk kemi; Astronomi; Astronomy; spektroskopi; magnetisk resonans; supraledare; magnetiska och optiska ; egenskaper elektriska; space research; cosmic chemistry; stellar magnetic fields; branching fractions; spectral line structure; Fysicumarkivet A:2002:Nielsen; Condensed matter:electronic structure; line blending; electrical;

    Abstract : This thesis is a description of how knowledge of atomic physics can be used in a stellar spectrum analysis. Stellar investigations are spectroscopically performed based on wavelengths, intensities and spectral line structure. READ MORE