Sökning: "stars: statistics"

Visar resultat 1 - 5 av 10 uppsatser innehållade orden stars: statistics.

  1. 1. Error propagation in nuclear models

    Kandidat-uppsats, Lunds universitet/Matematisk fysik; Lunds universitet/Fysiska institutionen

    Författare :Artis Mucenieks; [2023]
    Nyckelord :Physics and Astronomy;

    Sammanfattning : In this thesis we perform error analysis of a nuclear model based on density-functional theory developed in Lund. The Lund model allows us to perform calculations of nuclear spectra more efficiently by constructing a simple effective Hamiltonian reproducing the quadrupole deformation and pairing interaction strength parameters of a spherical Hartree-Fock reference functional. LÄS MER

  2. 2. Colliding Galaxies in a (Nut)Shell

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

    Författare :Jonathan Petersson; [2022]
    Nyckelord :shell galaxies; simulations; starbursts; quenching; mergers; Physics and Astronomy;

    Sammanfattning : Galaxy interactions and mergers are natural recurring events in the current cosmological paradigm, events that often coincide with starbursts and enhanced star formation activity. To understand why that is, one can use idealised (non-cosmological) merger simulations, which provide freedom to recreate specific tidally distorted galaxies, and analysis of the time evolution and underlying physics of the star formation activity at a high spatial resolution. LÄS MER

  3. 3. Examining LUMBA UVES pipeline spectroscopy on giant and sub-giant stars of M67

    Master-uppsats, Uppsala universitet/Observationell astrofysik

    Författare :Nikolaos Papakonstantinou; [2021]
    Nyckelord :methods: numerical; stars:abundances; stars: atmospheres; stars: statistics; stars:giants; stars:subgiants; stars: open clusters; stars: M67;

    Sammanfattning : In this work, the efficiency of the LUMBA UVES pipeline for processing of spectroscopic observations is tested by use on 23 high-resolution spectra of the open star cluster M67. An abundance trend discovered by Gavel et al. (2019) concerning iron abundances of giant and sub-giant stars of that cluster is examined. LÄS MER

  4. 4. An introduction to some ordinary differential equations governing stellar structures

    Kandidat-uppsats, Lunds universitet/Matematik (naturvetenskapliga fakulteten)

    Författare :Yani di Giovanni; [2019]
    Nyckelord :Mathematics and Statistics;

    Sammanfattning : The Lane-Emden equation is a non-linear differential equation governing the equilibrium of polytropic stationary self-gravitating, spherically symmetric star models; $${\frac {1}{\xi ^{2}}}{\frac {d}{d\xi }}\left({\xi ^{2}{\frac {d\theta }{d\xi }}}\right)+\theta ^{n}=0.$$ In the isothermal cases we have the Chandrasekhar equation: $${\frac {1}{\xi ^{2}}}{\frac {d}{d\xi }}\left({\xi ^{2}{\frac {d\psi}{d\xi }}}\right)-e^{-\psi}=0$$ After having derived these models, we will go through all cases for which analytic solutions are achievable. LÄS MER

  5. 5. Detailed analysis of the chemical composition of stars harboring Earth-like planets

    Master-uppsats, Lunds universitet/Astronomi - Genomgår omorganisation

    Författare :Lorena Acuña Aguirre; [2019]
    Nyckelord :Physics and Astronomy;

    Sammanfattning : Context. The planet-metallicity correlation for gaseous giants is widely accepted through spectroscopic studies. However, whether a similar correlation exists for terrestrial planets is a debated subject. LÄS MER