Sökning: "Interstellar gas"

Visar resultat 1 - 5 av 10 uppsatser innehållade orden Interstellar gas.

1. 1. Measuring copper abundances in the Galactic Bulge

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

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

   Sammanfattning : 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. LÄS MER

3. 2. 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

4. 3. The Milky Way and its Exoplanets

   Master-uppsats, Lunds universitet/Astronomi - Genomgår omorganisation

   Författare :Jesper Nielsen; [2021]
   Nyckelord :Planets and Satellites; Exoplanets; Occurrence Rates; Physics and Astronomy;

   Sammanfattning : The detections of over 4000 exoplanets as of today has shown that they exist in a wide range of different configurations, otherwise known as architectures. Recently, studies have been made trying to link the environment of host stars to the architectures of their planetary systems and have found that the architectures of planetary systems may not necessarily be uniform in the Milky Way. LÄS MER

5. 4. Effects of planetary radius contraction on scattering

   Kandidat-uppsats, Lunds universitet/Astronomi - Genomgår omorganisation

   Författare :Viktor Hrannar Jónsson; [2020]
   Nyckelord :Physics and Astronomy;

   Sammanfattning : The observed high orbital eccentricities of many giant exoplanets is thought to be the result of gravitational scattering between planets. Outcomes of planet-planet scattering can result in some planets being lost by ejections into interstellar space, or collisions between planets or with the star. LÄS MER

7. 5. Pulsation Properties in Asymptotic Giant Branch Stars

   Kandidat-uppsats, Uppsala universitet/Teoretisk astrofysik

   Författare :Ofelia Norgren; [2019]
   Nyckelord :Astronomy; Asymptotic Giant Branch stars; Stellar Evolution; Variable Stars; Power Spectrum;

   Sammanfattning : Asymptotic Giant Branch (AGB) stars are stars with low- to intermediate mass in a late stage in their stellar evolution. An important feature of stellar evolution is the ongoing nucleosynthesis, the creation of heavier elements. LÄS MER