Sökning: "negative ions"

Visar resultat 1 - 5 av 115 avhandlingar innehållade orden negative ions.

  1. 1. Precision measurements on negative ions

    Författare :Moa Kristiansson; Henning T. Schmidt; Dag Hanstorp; Henning Zettergren; Christophe Blondel; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Negative ions; Atomic physics; Precision measurement; Electron affinity; Photodetachment; Physics; fysik;

    Sammanfattning : In this thesis, experiments with negative ions performed at the DESIREE facility are presented. DESIREE consists of two electrostatic storage rings operated at 13 K. The low temperature in combination with a low pressure allows for storage times of the negative ion beams to be up to several hours. LÄS MER

  2. 2. Excited States in Negative Ions

    Författare :Johan Rohlén; Göteborgs universitet; Göteborgs universitet; Gothenburg University; []
    Nyckelord :Negative Ions; Photodetachment; Atomic Physics; Experimental Physics;

    Sammanfattning : This thesis covers experimental studies of atomic negative ions with the main goal of increasing our fundamental understanding of these fragile quantum systems. Comparisons of measurements and calculations have been used to increase our understanding of these highly correlated, yet simple, systems. LÄS MER

  3. 3. Negative Ions Interacting with Photons and Electrons

    Författare :Anton Lindahl; Göteborgs universitet; Göteborgs universitet; Gothenburg University; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Negative ions; electron correlation; electron affinity; photodetachment; electron collision;

    Sammanfattning : Negative ions are atoms or molecules where an extra electron is bound to neutral system. The nature of negative ions differs fundamentally from neutral and positive systems. The induced dipole potential responsible for the binding of the extra electron supports only a few bound states with relatively small binding energies. LÄS MER

  4. 4. Laser Photodetachment of Negative Ions - Fundamental Research and Applications

    Författare :Pontus Andersson; Göteborgs universitet; Göteborgs universitet; Gothenburg University; []
    Nyckelord :Negative Ions; Laser Spectroscopy; Photodetachment; Electron Affinity; Mass Spectrometry; Radiative Lifetime; Storage Rings;

    Sammanfattning : Photodetachment studies of atomic and molecular negative ions in the gas phase are presented. Negative ions are loosely bound quantum systems whose existence is strongly dependent on the correlations between the electrons. LÄS MER

  5. 5. Resonant States in Negative Ions

    Författare :Nicklas Brandefelt; John S. Briggs; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Molekylfysik; Atomfysik; Kärnfysik; Partikelfysik; Atomic and molecular physics; Atom- och molekylfysik;

    Sammanfattning : Resonant states are multiply excited states in atoms and ions that have enough energy to decay by emitting an electron. The ability to emit an electron and the strong electron correlation (which is extra strong in negative ions) makes these states both interesting and challenging from a theoretical point of view. LÄS MER