Sökning: "Atomic structure"

Visar resultat 1 - 5 av 605 avhandlingar innehållade orden Atomic structure.

  1. 1. Theoretical Atomic Spectroscopy of Earthbound and Stellar Plasma

    Författare :Jon Grumer; Matematisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; atomstruktur; atomära processer; elektronkorrelation; plasmaspektroskopi; magnetfält; hyperfinstruktur; solkoronan; rymdväder; förekomst av grundämnen i stjärnor; datorsimuleringar; Zeemaneffekt; relativistiska effekter; atomic structure; atomic processes; computer simulation; electron correlation; relativistic atomic theory; plasma spectroscopy; Zeeman effect; magnetic fields; hyperfine structure; solar corona; space weather; stellar abundances; Fysicumarkivet A:2016:Grumer;

    Sammanfattning : Motivated by spectroscopic analysis of astrophysical and laboratory plasma, this thesis concerns the fundamental structure and spectral properties of atoms and their ions. The multiconfiguration Dirac-Hartree-Fock (MCDHF) method is used to predict the emission or absorption of radiation, by atomic systems in general, and of heavy and highly charged ions in particular. LÄS MER

  2. 2. Weak Atomic Interactions

    Författare :Peter Schef; Sven Mannervik; Juliet C. Pickering; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; metastable states; forbidden transitions; laser probing; hyperfine structure; LRDR; Atomic physics; Atomfysik;

    Sammanfattning : An atom or ion can change quantum state, usually through emission or absorption of a photon. The photon has the same energy as the energy difference between the states of the transition. The states, or energy levels, of an atom are quantized and light emitted, or absorbed, from the atom is therefore of specific wavelengths, giving spectral lines. LÄS MER

  3. 3. Theoretical Studies of Atomic Structure, Radiative Transitions and Interference Effects

    Författare :Martin Andersson; Fysiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Naturvetenskap; Natural science; Computational physics; Zeeman; Transition rate; Lifetime; Hyperfine structure; Interference; Atomic structure;

    Sammanfattning : Theoretical calculations concerning the advanced understanding of atomic structure and transitions has been performed for some atomic systems. The importance of different types of correlation depending on system has been investigated both using relativistic and non-relativistic quantum mechanics. LÄS MER

  4. 4. Formation stability and electronic structure of surfaces and interfaces from first principles

    Författare :Jochen Rohrer; Chalmers University of Technology; []
    Nyckelord :NATURVETENSKAP; TEKNIK OCH TEKNOLOGIER; NATURAL SCIENCES; ENGINEERING AND TECHNOLOGY; band structure; van der Waals interaction; electronic structure; graphane; graphene; atomic structure; growth; thin film; interface; density functional theory; CVD; Alumina; nucleation;

    Sammanfattning : This thesis deals with two closely interwoven aspects of first-principle(density functional theory) materials modeling:(1)~prediction of atomic structure & chemical composition,and (2)~prediction of electronic properties.In the first part, we focus on atomic structure (AS) and chemical composition (CC) of surface and interface systems. LÄS MER

  5. 5. Atomic Electrons as Sensitive Probes of Nuclear Properties and Astrophysical Plasma Environments : A Computational Approach

    Författare :Asimina Papoulia; Matematisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fysicumarkivet A:2021:Papoulia; Computational atomic structure; Relativistic atomic theory; Transition probabilities; Abundance analysis; Landé g­-factors; Hyperfine structure; Nuclear quadrupole moments; Isotope shift; Field shift; Nuclear deformation;

    Sammanfattning : This thesis deals with the relativistic modeling of atoms and ions. To interpret the stellar spectra and gain more insight from astrophysical observations, the underlying processes that generate the spectra need to be well understood and described. LÄS MER