Sökning: "stars: open clusters"

Hittade 5 uppsatser innehållade orden stars: open clusters.

1. 1. The chemical evolution of the Milky Way: pushing APOGEE to higher precision and accuracy

   Master-uppsats, Lunds universitet/Astrofysik; Lunds universitet/Fysiska institutionen

   Författare :Erik Fridén; [2023]
   Nyckelord :Physics and Astronomy;

   Sammanfattning : In the recent decade, a rapid increase in all-sky spectroscopic surveys has occurred, and with it, the wealth of observational data and information on our Galaxy. Consequently, numerous detections of new structures, such as new open clusters, accreted and in-situ components, are discovered. LÄS MER

3. 2. Origin of blue straggler stars in the Milky Way halo

   Master-uppsats, Lunds universitet/Astrofysik; Lunds universitet/Fysiska institutionen

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

   Sammanfattning : 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

4. 3. Blue Stragglers from Primordial Binary Evolution

   Kandidat-uppsats, Lunds universitet/Astronomi - Genomgår omorganisation

   Författare :Emilie Desrochers Karlsson; [2022]
   Nyckelord :blue stragglers; binary; stars; binary evolution; mass transfer; Physics and Astronomy;

   Sammanfattning : Blue stragglers were first discovered as hotter and more luminous than the turnoff in the globular cluster M3. Their presence is typically explained by the interplay between stellar collisions and mass transfer in binary systems. In this thesis, I study blue stragglers produced from primordial binary evolution. LÄS MER

5. 4. Examining LUMBA UVES pipeline spectroscopy on giant and sub-giant stars of M67

   Master-uppsats, Uppsala universitet/Observationell astrofysik

   Författare :Nikolaos Papakonstantinou; [2021]
   Nyckelord :methods: numerical; stars:abundances; stars: atmospheres; stars: statistics; stars:giants; stars:subgiants; stars: open clusters; stars: M67;

   Sammanfattning : In this work, the efficiency of the LUMBA UVES pipeline for processing of spectroscopic observations is tested by use on 23 high-resolution spectra of the open star cluster M67. An abundance trend discovered by Gavel et al. (2019) concerning iron abundances of giant and sub-giant stars of that cluster is examined. LÄS MER

7. 5. N-body Simulations in Galactic Potentials

   Kandidat-uppsats, Lunds universitet/Astronomi - Genomgår omorganisation

   Författare :David Andersson; [2019]
   Nyckelord :N-body; simulation; spen clusters; dissolving time; Hyades; members of the Hyades; double integration; Physics and Astronomy;

   Sammanfattning : What effect does a collision between two clusters have on their dissolving time? In order to answer this question, a new type of N-body simulation using a double integration of a cluster was built. Instead of introducing a perturbation representing the gravitational force of the Milky Way into a local simulation of the cluster, the cluster orbit was integrated in the potential of the Milky Way, and in each of these integration steps the local motion of the stars inside the cluster were integrated, using an N-body calculation. LÄS MER