Sökning: "Absorption Spectrum"

Visar resultat 1 - 5 av 72 uppsatser innehållade orden Absorption Spectrum.

  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. Wavelength-dependent limb darkeningin the analysis oftransit spectroscopy of exoplanets

    L3-uppsats, Uppsala universitet/Institutionen för fysik och astronomi

    Författare :Alberto García Ribas; [2023]
    Nyckelord :;

    Sammanfattning : Limb darkening, an optical effect characteristic of stars, where the limb (edge) seemsto be darker than the centre of the stellar body; plays an important role in our under-standing of exoplanetary transits, as it is fundamental for developing light curve modelsthat can help to undercover extrasolar companions. To recover atmospheric featuresfrom exoplanets, a principal component analysis method is typically used. LÄS MER

  4. 3. Using the James Webb Space Telescope to Find Carbon Dioxide on Ganymede

    Kandidat-uppsats, KTH/Skolan för elektroteknik och datavetenskap (EECS)

    Författare :Olof Helgesson; Oscar Lundin; [2023]
    Nyckelord :;

    Sammanfattning : The aim of this bachelor's thesis is to search for CO₂ on Ganymede by studyingobservations taken by the James Webb Space Telescope and in doing so, create aprocessing pipeline for JWST data. The data is collected by JWST's Near InfraredSpectrograph instrument which is used for spectroscopy in the near infrared spectrum. LÄS MER

  5. 4. Improving the experimental setup for ultrasound-optical tomography imaging

    Uppsats för yrkesexamina på avancerad nivå, Luleå tekniska universitet/Institutionen för teknikvetenskap och matematik

    Författare :Ibtisam Dahir Ahmed; [2023]
    Nyckelord :Ultrasound-optical tomography UOT ; thulium-doped lithium niobate;

    Sammanfattning : According to Bröstcancer förbundet, mammography is not efficient at detecting tumors in dense breast tissue or diagnosing breast cancer at its early stages. Ultrasound-optical tomography (UOT) is an imaging technique in development and has the potential for deep-tissue imaging. LÄS MER

  7. 5. Fabry Pérot Nanocavity Produced via Solution Methods

    Master-uppsats, Uppsala universitet/Materialfysik; Uppsala universitet/Fysikalisk kemi

    Författare :Stylianos Kioumourtzoglou; [2023]
    Nyckelord :Plasmonics; Photocatalyis; Fabry Pérot nanocavity;

    Sammanfattning : Plasmonics have attracted significant attention from the scientific community for photoelectrode technologies since they offer tunability, large light absorption cross-sections, transparency and potential scalability. On the downside, plasmonics exhibit large absorption cross sections in a narrow window compared to the total electromagnetic spectrum, leading to relatively small efficiencies. LÄS MER