Sökning: "Stellar Temperature"

Visar resultat 1 - 5 av 29 uppsatser innehållade orden Stellar Temperature.

  1. 1. The visibility of stellar transients in the Galactic Centre

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

    Författare :Jonathan Ström; [2024]
    Nyckelord :Physics and Astronomy;

    Sammanfattning : A semi-analytical simulation was developed to evaluate the K-band magnitudes of Red Giants [0.96 - 1.02 M⊙] orbiting the supermassive black hole in the galactic centre. The model assumed star formation between 10-12 Gyrs ago and by following the IMF and applying a random age condition, a stellar population was created. LÄS MER

  3. 2. Starshades: Geoengineering Solutions and Technosignatures in Direct Imaging Phase Curves

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

    Författare :Claudia Skoglund; [2023]
    Nyckelord :Starshades; extraterrestrial intelligence; stellar evolution; technosignatures; phase curves; direct imaging; habitable zone.; Physics and Astronomy;

    Sammanfattning : The stellar luminosity increases as a star evolves which inevitably yields a higher temperature on planets in orbit around the star. It is reasonable to assume that intelligent civilizations would tackle this issue through installing artificial structures that can alter the radiation received by the planet. LÄS MER

  4. 3. 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

  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. An Infrared Stellar Thermometer: Exploiting IGRINS Spectra

    Kandidat-uppsats, Lunds universitet/Astronomi - Genomgår omorganisation

    Författare :Emelie Sandved; [2022]
    Nyckelord :Effective temperature; K-giants; surface gravity; oxygen abundance; carbon abundance; CO lines; OH lines; line sensitivities; Physics and Astronomy;

    Sammanfattning : Using the infrared (IR) spectral range when measuring stellar spectra is beneficial compared to using the optical range mainly when observing distant stars through the dust dense interstellar regions in the Galactic mid-plane. Methods to determine stellar parameters from IR spectra are, however, not fully developed yet because technological difficulties in creating reliable IR detectors have slowed the advance of such methods. LÄS MER