Sökning: "Dwarf Stars"
Visar resultat 1 - 5 av 33 uppsatser innehållade orden Dwarf Stars.
1. Measuring copper abundances in the Galactic Bulge
Kandidat-uppsats, Lunds universitet/Astrofysik; Lunds universitet/Fysiska institutionenSammanfattning : Context: The chemical evolution of Cu in the Galactic bulge have been studied in a few studies using red giant branch stars, but the ages of individual red giant stars are difficult to determine. In addition, the bulge has been a challenging region of the Milky Way galaxy to obtain high-resolution spectra of stars, except when observing through certain few small fields into the bulge that are known to have low extinction. LÄS MER
2. The quest for a classical bulge - a study of kinematics, abundances, and ages using microlensed dwarf stars and Gaia
Master-uppsats, Lunds universitet/Astrofysik; Lunds universitet/Fysiska institutionenSammanfattning : Context: We present an kinematical analysis of 90 F and G type dwarf, turn-off, and subgiant stars in the Galactic bulge. These stars were observed with high-resolution spectrographs during gravitational microlensing events This allowed for their ages, abundances, and radial velocities to be ascertained while they were significantly brighter. LÄS MER
3. Wavelength-dependent limb darkeningin the analysis oftransit spectroscopy of exoplanets
L3-uppsats, Uppsala universitet/Institutionen för fysik och astronomiSammanfattning : Limb darkening, an optical effect characteristic of stars, where the limb (edge) seemsto be darker than the centre of the stellar body; plays an important role in our under-standing of exoplanetary transits, as it is fundamental for developing light curve modelsthat can help to undercover extrasolar companions. To recover atmospheric featuresfrom exoplanets, a principal component analysis method is typically used. LÄS MER
4. Potassium in the Galactic Bulge - as traced by microlensed dwarf & sub-giant stars
Kandidat-uppsats, Lunds universitet/Astrofysik; Lunds universitet/Fysiska institutionenSammanfattning : During this report the potassium (K) trend in the Galactic Bulge, with respect to metallicity and various α-elements, has been computed and evaluated by a method of line synthesis on the 7698.96 ̊A KI line (7699 KI), where Non-Local-Thermal-Equilibrium (NLTE) effects have been considered. LÄS MER
5. Origin of blue straggler stars in the Milky Way halo
Master-uppsats, Lunds universitet/Astrofysik; Lunds universitet/Fysiska institutionenSammanfattning : Blue straggler stars (BSSs) are exotic stellar objects that appear to be younger than the age of the population they come from suggests. They are observed as the extension of the main sequence stars, beyond the turn-off point. LÄS MER
