Sökning: "Binary stellar evolution"

Visar resultat 1 - 5 av 13 uppsatser innehållade orden Binary stellar evolution.

1. 1. What limits the luminosity of red supergiants?

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

   Författare :Eric Svensson; [2023]
   Nyckelord :Stellar evolution; Red supergiants; Red giants; Luminosity; Binary stars; Binary star systems; Binary star interactions; Binary stellar evolution; Humphreys-Davidson limit; Upper luminosity limit; BSE; Population synthesis; Simulations; M31; LMC; SMC; Metallicity; Mass transfer; Merging; Physics and Astronomy;

   Sammanfattning : The observed upper limit of the luminosity of red supergiants, often called the Humphreys-Davidson limit, has recently been shown to be independent of metallicity and to not be explainable by single star evolution – findings that both contradict established ideas of the origins of the limit. It is now known that the vast majority of stars with sufficient mass to possibly evolve into red supergiants above the limit interact with companion stars at some point during their lives. LÄS MER

3. 2. Intermediate-mass black hole binary as an origin of super-massive black holes

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

   Författare :Isabelle Signe Maj Maria Thord; [2023]
   Nyckelord :Intermediate-mass black holes; binary; merger; hardening; encounters; Physics and Astronomy;

   Sammanfattning : Galactic nuclei contain super-massive black holes (SMBHs), nuclear stellar clusters (NSCs), or both. In the NSC, intermediate-mass black holes (IMBHs) are likely to reside and form highly eccentric binaries. Over time, the orbit of a binary could harden via interaction with surrounding low-mass stars. LÄS MER

4. 3. 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

5. 4. Black Hole Dynamics in Stellar Clusters

   Master-uppsats, Lunds universitet/Institutionen för astronomi och teoretisk fysik - Genomgår omorganisation; Lunds universitet/Astronomi - Genomgår omorganisation

   Författare :Markus Strickert; [2022]
   Nyckelord :Black Holes; Globular Clusters; Dynamics; Intermediate-mass black holes; Simulations; Physics and Astronomy;

   Sammanfattning : Star clusters can harbour many exotic objects, including black holes (BHs), X-ray binaries and blue straggler stars. In dense stellar environments like globular clusters (GCs), two-body relaxation drives their dynamical evolution, where gravitational interactions between stars strive to equalize their kinetic energy in the cluster. LÄS MER

7. 5. 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