Essays about: "Dwarf Stars"

Showing result 1 - 5 of 33 essays containing the words Dwarf Stars.

1. 1. Measuring copper abundances in the Galactic Bulge

   University essay from Lunds universitet/Astrofysik; Lunds universitet/Fysiska institutionen

   Author : Nikolei Höglinger; [2024]
   Keywords : Copper; Galaxy: abundances; Galaxy: bulge; Chemical Evolution; Physics and Astronomy;

   Abstract : 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. READ MORE

3. 2. The quest for a classical bulge - a study of kinematics, abundances, and ages using microlensed dwarf stars and Gaia

   University essay from Lunds universitet/Astrofysik; Lunds universitet/Fysiska institutionen

   Author : Calum Kvernes Macpherson; [2023]
   Keywords : Bulge; Milky Way; Kinematics; Galpy; Dwarf Stars; Physics and Astronomy;

   Abstract : 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. READ MORE

4. 3. Wavelength-dependent limb darkeningin the analysis oftransit spectroscopy of exoplanets

   University essay from Uppsala universitet/Institutionen för fysik och astronomi

   Author : Alberto García Ribas; [2023]
   Keywords : ;

   Abstract : 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. READ MORE

5. 4. Potassium in the Galactic Bulge - as traced by microlensed dwarf & sub-giant stars

   University essay from Lunds universitet/Astrofysik; Lunds universitet/Fysiska institutionen

   Author : Lukas Jönsson; [2023]
   Keywords : Nucleosynthesis; Galactic Bulge; Potassium; Non-Local-Thermal-Equilibrium; Physics and Astronomy;

   Abstract : 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. READ MORE

6. 5. Origin of blue straggler stars in the Milky Way halo

   University essay from Lunds universitet/Astrofysik; Lunds universitet/Fysiska institutionen

   Author : Adam Brcek; [2023]
   Keywords : Blue Straggler; Galactic Halo; Spectroscopic Surveys; Binary Star Evolution; Mass Transfer; Physics and Astronomy;

   Abstract : 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. READ MORE