Sökning: "Omorganisation"

Visar resultat 1 - 5 av 147 avhandlingar innehållade ordet Omorganisation.

1. 1. A study of the Hercules dwarf spheroidal galaxy

   Författare :Daniel Adén; Astronomi - Genomgår omorganisation; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : Parts of large spiral galaxies, such as the Milky Way and Andromeda, are believed to have formed from the accretion of several smaller galaxies. Remnants of this chaotic merging era, such as dwarf spheroidal (dSph) galaxies, are visible in the outskirts of large galaxies. LÄS MER

3. 2. A study of the new dwarf spheroidal galaxy in Hercules - metallicity and a stellar inventory

   Författare :Daniel Adén; Astronomi - Genomgår omorganisation; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : Not available.... LÄS MER

4. 3. Measurements of High-Precision Atomic Data with Applications to Astrophysics and Cosmology

   Författare :Maria Aldenius; Astronomi - Genomgår omorganisation; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; atomic data; Ca; Cr; Fe; Mn; Mg; metal-poor stars; fine-structure constant; Fourier transform spectroscopy; nebulae; oscillator strengths; spectroscopy; wavelengths; Ti; Zn; Astronomy; Astronomi; Atomic and molecular physics; Atom- och molekylärfysik; rymdvetenskap; space research; cosmic chemistry; kosmisk kemi; branching fractions;

   Sammanfattning : Investigations of astrophysical spectra require accurate atomic data, such as wavelengths and transition probabilities. This thesis provides high-precision atomic data for astrophysical and cosmological applications. The measurements have been carried out using Fourier transform spectrometry on light produced in a hollow cathode light source. LÄS MER

5. 4. The galactic scale impact of feedback from individual stars

   Författare :Eric Andersson; Astronomi - Genomgår omorganisation; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; galaxies; galaxy evolution; galactic winds; interstellar medium; star formation; stellar feedback; runaway stars; numerical modelling;

   Sammanfattning : Feedback from stars is essential for the formation and evolution of galaxies. It is an energy source that drives gas motions and chemically enriches the galaxy by supplying metals. Without this stellar feedback, numerical galaxy simulations result in galaxies with little resemblance to those observed in our Universe. LÄS MER

7. 5. A Photometric Study of the Galactic Disks based on Strömgren Photometry

   Författare :Anna Arnadottir; Astronomi - Genomgår omorganisation; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; density parameters; formation.; metallicity distribution function; thin disk; metallicities. Galaxy - thick disk; colours; Photometry - Strömgren; luminosities; SDSS. Stars - classification;

   Sammanfattning : One of the key questions in todays galaxy research is the formation and evolution of disk galaxies such as the Milky Way. Using observations in the intermediate band Stromgren uvby filter system we have investigated how both density and metallicity varies within the Galactic disks in order to learn more about the Galaxy and its past. LÄS MER