Sökning: "Stjärnor"

Visar resultat 16 - 20 av 145 uppsatser innehållade ordet Stjärnor.

1. 16. An Infrared Stellar Thermometer: Exploiting IGRINS Spectra

   Kandidat-uppsats, Lunds universitet/Astronomi - Genomgår omorganisation

   Författare :Emelie Sandved; [2022]
   Nyckelord :Effective temperature; K-giants; surface gravity; oxygen abundance; carbon abundance; CO lines; OH lines; line sensitivities; Physics and Astronomy;

   Sammanfattning : Using the infrared (IR) spectral range when measuring stellar spectra is beneficial compared to using the optical range mainly when observing distant stars through the dust dense interstellar regions in the Galactic mid-plane. Methods to determine stellar parameters from IR spectra are, however, not fully developed yet because technological difficulties in creating reliable IR detectors have slowed the advance of such methods. LÄS MER

3. 17. Detecting Transiting Exoplanets in Crowded Fields

   Kandidat-uppsats, Lunds universitet/Astronomi - Genomgår omorganisation

   Författare :Eddie Larsson; [2022]
   Nyckelord :Transit method; Globular cluster; crowded environments; exoplanets; transiting exoplanets; Physics and Astronomy;

   Sammanfattning : The first planet orbiting a main-sequence star was discovered in 1995. Since then more than 4000 additional exoplanets have been discovered. This is a rapidly evolving field in astrophysics. One of the most common ways to detect an exoplanet is through transit, as the brightness of the host star decreases. LÄS MER

4. 18. Quantum Gauge Fields in Cosmology: Cosmic Inflation and Gravitational Waves

   Kandidat-uppsats, Lunds universitet/Teoretisk partikelfysik - Geonomgår omorganisation

   Författare :Emma Hermansson; [2022]
   Nyckelord :Physics and Astronomy;

   Sammanfattning : In this thesis, the consequences of introducing Yang-Mills fields into cosmology are investigated. This is done by the effective action approach, in which the coupling constant is allowed to depend on the quantum fields. LÄS MER

5. 19. The Metallicity Structure of the Milky Way Halo II : Characterising the distant halo substructure

   Master-uppsats, Uppsala universitet/Observationell astrofysik

   Författare :Amanda Byström; [2022]
   Nyckelord :Milky Way; Galactic archaeology; halo; photometric metallicities; stellar catalogue; Gaia-Enceladus-Sausage; Sagittarius; Pristine survey; metallicity; Gaia mission;

   Sammanfattning : The Milky Way galaxy, like all spiral galaxies, is surrounded by a roughly spherical distribution of stars called the halo. The halo was largely formed when the galaxy merged with smaller galaxies. LÄS MER

7. 20. On The Run: How Fast Runaway Stars Can Escape From Their Home Cluster?

   Kandidat-uppsats, Lunds universitet/Astronomi - Genomgår omorganisation

   Författare :Anna-Maria Söderman; [2022]
   Nyckelord :star cluster; runaway stars; velocity distribution; Physics and Astronomy;

   Sammanfattning : Galaxies contain a wide variety of star clusters with different properties. Each cluster is a possible source of runaway stars, which can be progenitors of supernovae in other parts of the galaxy than their home cluster. Considering runaway stars in galaxy simulations has shown to increase the galactic feedback. LÄS MER