Sökning: "Atomic and molecular physics"

Visar resultat 1 - 5 av 388 avhandlingar innehållade orden Atomic and molecular physics.

  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; 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. Nanostructures of Graphite and Amorphous Carbon - Fabrication and Properties

    Författare :Hans Fredriksson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; optical resonance; Raman-spectrum; carbon; optical spectrum; HOPG; GC amorphous carbon; oxidation; Nanofabrication;

    Sammanfattning : Nanoscience is a well-established research area, which concerns properties and fabrication of objects with typical dimensions on the 1-100 nanometer length scale. A central issue has been the development of techniques for fabrication and characterization of nanometer sized objects, which have contributed considerably to progress in both practical applications and fundamental research. LÄS MER

  3. 3. Extreme Electron Beams and Brilliant X-rays : Generation, Manipulation and Characterization of Relativistic Electron Beams for and from Plasma-Based Accelerators

    Författare :Jonas Björklund Svensson; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; laser; plasma; wakefield; acceleration; accelerator; relativistic; electrons; x-rays; ultra-fast; betatron; laser-wakefield acceleration; plasma-wakefield acceleration; Fysicumarkivet A:2020:Björklund;

    Sammanfattning : This thesis is based on work done by the author on the development of plasma-based electron accelerators driven by ultra-intense laser pulses and dense electron bunches. Plasma based accelerators have several benefits, such as accelerating fields around 1000 times stronger than in “conventional” radio-frequency accelerators, which can allow for shrinking the overall footprint of the accelerator. LÄS MER

  4. 4. Solving the quantum scattering problem for systems of two and three charged particles

    Författare :Mikhail Volkov; Nils Elander; William McCurdy; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Scattering theory; three body scattering; Atomic and molecular physics; Atom- och molekylfysik; Mathematical physics; Matematisk fysik; fysik; Physics;

    Sammanfattning : A rigorous formalism for solving the Coulomb scattering problem is presented in this thesis. The approach is based on splitting the interaction potential into a finite-range part and a long-range tail part. In this representation the scattering problem can be reformulated to one which is suitable for applying exterior complex scaling. LÄS MER

  5. 5. Atomic Scale Design of Clean Energy Materials : Efficient Solar Energy Conversion and Gas Sensing

    Författare :Jawad Nisar; Rajeev Ahuja; Puru Jena; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Photocatalysts; Band gap narrowing; Water dissociation; Density functional theory; Gas sensing; Kaolinite; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : The focus of this doctoral thesis is the atomic level design of photocatalysts and gas sensing materials. The band gap narrowing in the metal oxides for the visible-light driven photocatalyst as well as the interaction of water and gas molecules on the reactive surfaces of metal oxides and the electronic structure of kaolinite has been studied by the state-of-art calculations. LÄS MER