Sökning: "Stellar Spectroscopy"

Visar resultat 1 - 5 av 17 uppsatser innehållade orden Stellar Spectroscopy.

  1. 1. Collisional broadening by hydrogenfor stellar spectroscopy : extension towards high-lying states

    Kandidat-uppsats, Uppsala universitet/Teoretisk astrofysik

    Författare :Adam Hultquist; [2019]
    Nyckelord :Astrophysics; Spectral line broadening; ABO; Collisional broadening;

    Sammanfattning : The object of this thesis is to extend the current tables for two useful quantities when calculatingcollisional broadening, the cross-section of interaction and the velocity parameter.These quantities, which have hitherto been tabulated for lower states, have now been calculatedfor higher lying states and are used in the ABO - model for spectral line broadening. LÄS MER

  2. 2. Detailed chemical abundances of neutron-capture elements - from 523 local giant stars

    Master-uppsats, Lunds universitet/Astronomi

    Författare :Rebecca Forsberg; [2019]
    Nyckelord :The Milky Way galaxy; Abundances; High-resolution spectroscopy; Neutron-capture elements; Physics and Astronomy;

    Sammanfattning : Purpose: The purpose of this work is to determine the abundances of neutron-capture elements in solar neighborhood giant stars. This enables constraints to be put on the the cosmic origin of these elements. LÄS MER

  3. 3. Spectroscopy of the Globular Cluster M30

    Master-uppsats, Uppsala universitet/Observationell astrofysik

    Författare :Kilian Hikaru Scheutwinkel; [2019]
    Nyckelord :Spectroscopy; Globular Cluster; M30;

    Sammanfattning : Globular Clusters contain very old metal-poor stars in different evolutionary stages evolved from the same primordial cloud. Signatures of atomic in stellar interiors are studied in the metal-poor GC M30. Furthermore, traces of cluster internal pollution depleting alpha elements e.g. LÄS MER

  4. 4. Implementing an Algorithm for Spectrum Extraction of Circumstellar Objects with High-Dispersion Spectroscopy

    Master-uppsats, Stockholms universitet/Institutionen för astronomi

    Författare :Marcus Karlsson; [2019]
    Nyckelord :Astronomy; Spectroscopy; Exoplanets; Circumstellar Objects; Direct Imaging;

    Sammanfattning : In this thesis project, we study the field of high-dispersion spectroscopy and methods for extracting the spectrum of circumstellar objects such as exoplanets from the combined signal of a stellar system. One of the only techniques for detecting absorption lines in exoplanetary atmospheres is to directly image a planet and record the reflected light. LÄS MER

  5. 5. Conditions for detecting population III galaxies with next-generation telescopes

    Master-uppsats, Uppsala universitet/Observationell astrofysik

    Författare :Emma Fransson; [2019]
    Nyckelord :population III stars galaxies WFIRST;

    Sammanfattning : Through the spectral synthesis model YGGDRASIL, developed by E. Zackris- son et al. 2011, luminosities for the chemically pristine population III galaxies are retrieved and compared to the capabilities of the upcoming infrared telescopes, in particluar the Wide Field InfraRed Survey Telescope (WFIRST). LÄS MER