Sökning: "Stellar Halo"

Visar resultat 1 - 5 av 19 uppsatser innehållade orden Stellar Halo.

1. 1. Finding new members of the VelHel-4 stream

   Kandidat-uppsats, KTH/Skolan för teknikvetenskap (SCI)

   Författare :Lucas Johansson; [2023]
   Nyckelord :Galactic Archaeology; Milky Way; Stellar Streams; Streams; Stellar Halo; Stars; Globular Cluster; Astronomy; Astrophysics; Gaia; Chemical Abundance; Spectroscopy;

   Sammanfattning : According to the paradigm of lambda-CDM cosmology, the stellar halo ofour Galaxy has been built-up over time through the accretion of other galaxiesand star clusters. The remnants of some of these are still observable today asstellar streams, but are typically very faint and difficult to resolve amidst the farmore numerous foreground Milky Way stars. 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. Hyper-velocity stars from globular clusters hosting intermediate-mass black holes

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

   Författare :Matilda Skantz; [2023]
   Nyckelord :Hypervelocity stars; run-away stars; stellar binary; intermediate mass black hole; globular cluster; Hills mechanism; Physics and Astronomy;

   Sammanfattning : In 1988 Hills proposed that stars can gain velocities above 500 km s−1 if they are in a stellar binary which gets disrupted by a super massive black hole (SMBH). One of the stars would get trapped in an elliptical orbit around the SMBH while the other gets ejected and obtains a relatively high velocity. LÄS MER

5. 4. Black Holes of the First Stars

   Master-uppsats, Uppsala universitet/Institutionen för fysik och astronomi

   Författare :Aron Kordt; [2022]
   Nyckelord :;

   Sammanfattning : In this report, we constrain properties of foreground objects in the Milky Way that have the potential of being confused with accretion disks of Population III stellar- mass black holes at high redshift. Following Windhorst et al. (2018), a model for multicolour accretion disks of Population III stellar-mass black holes is presented. LÄS MER

7. 5. Starbursts at Cosmic Dawn : Formation of Globular Clusters, Ultra-Faint Dwarfs, and Population III star clusters at z > 6

   Master-uppsats, Stockholms universitet/Institutionen för astronomi

   Författare :Olof Nebrin; [2022]
   Nyckelord :Cosmology; Galaxy Formation; Globular Clusters; First Stars; Dark Matter; Cosmic Dawn; Reionization; Ultra-Faint Dwarfs;

   Sammanfattning : In the standard model of cosmology (ΛCDM) the first stars, star clusters, and galaxies are expected to have formed in short bursts of star formation in low-mass dark matter halos at high redshifts (). Up to this point, attempts to predict the properties and abundances of these luminous objects have made use of numerically expensive cosmological simulations. LÄS MER