Sökning: "Microlensing"

Hittade 5 uppsatser innehållade ordet Microlensing.

  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

  2. 2. The quest for a classical bulge - a study of kinematics, abundances, and ages using microlensed dwarf stars and Gaia

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

    Författare :Calum Kvernes Macpherson; [2023]
    Nyckelord :Bulge; Milky Way; Kinematics; Galpy; Dwarf Stars; Physics and Astronomy;

    Sammanfattning : Context: We present an kinematical analysis of 90 F and G type dwarf, turn-off, and subgiant stars in the Galactic bulge. These stars were observed with high-resolution spectrographs during gravitational microlensing events This allowed for their ages, abundances, and radial velocities to be ascertained while they were significantly brighter. LÄS MER

  3. 3. Spectroscopic model characterisation of hot exoplanet atmospheres

    Master-uppsats, Lunds universitet/Astronomi - Genomgår omorganisation; Lunds universitet/Fysiska institutionen

    Författare :Elin Sandvik; [2022]
    Nyckelord :Transit method; Transmission spectroscopy; Exoplanets; Hot Jupiter; Modelling; Physics and Astronomy;

    Sammanfattning : Hot Jupiters are gas giants under intense stellar radiation with short orbital periods of only a few days. Due to their large radii, hot temperatures, and large scale heights, hot Jupiters can be observationally characterised in detail through spectroscopy over an entire orbital phase. LÄS MER

  4. 4. A Close Look at the Transient Sky in a Neighbouring Galaxy

    Master-uppsats, Luleå tekniska universitet/Rymdteknik

    Författare :Kiran Tikare; [2020]
    Nyckelord :Astrophysical Transients; Optical Transients; Microlensing; Variable Stars; Andromeda Galaxy; Forced Aperture Photometry; Time Domain Astronomy; Sky Survey; Zwicky Transient Facility; Machine Learning; Big Data Science;

    Sammanfattning : Study of the time variable sources and phenomena in Astrophysics provides us with important insights into the stellar evolution, galactic evolution, stellar population studies and cosmological studies such as number density of dark massive objects. Study of these sources and phenomena forms the basis of Time Domain surveys, where the telescopes while scanning the sky regularly for a period of time provides us with positional and temporal data of various Astrophysical sources and phenomena happening in the Universe. LÄS MER

  5. 5. The astronomical consequences of primordial black holes

    Master-uppsats, Lunds universitet/Astronomi - Genomgår omorganisation

    Författare :Loke Lönnblad Ohlin; [2019]
    Nyckelord :Physics and Astronomy;

    Sammanfattning : In the radiation or early matter dominated eras of the Universe, there is a theoretical possibility for the formation of black holes (BHs). These primordial black holes (PBHs) have been thought of as a possible candidate for dark matter (DM), and an attractive one at that as it would explain DM using only baryonic physics. LÄS MER