Sökning: "Radiative Lifetimes"

Visar resultat 1 - 5 av 22 avhandlingar innehållade orden Radiative Lifetimes.

  1. 1. Radiative Properties of Rare Earth Elements - Free and Bound in Crystals

    Författare :Huailiang Xu; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Laser Spectroscopy; Upconversion; Lifetimes; Atomic and molecular physics; Atom- och molekylärfysik; Laser technology; Laserteknik; Rare earth Elements; Fysicumarkivet A:2004:Xu;

    Sammanfattning : This thesis is devoted to fundamental aspects, and to spectroscopic applications of radiative properties in free atoms and ions, as well as in ions doped into crystals. Using the time-resolved laser-induced fluorescence technique, measurements of radiative lifetimes for rare earth elements have been performed in neutral Pr, Nd, Tm, and in singly ionized Sm, Er, Nd, Tm, Yb, as well as in doubly ionized Tm and Tb ions. LÄS MER

  3. 2. Radiative lifetimes of bound excited states in anions : Measurements on long-lived metastable states in atomic anions

    Författare :Odd Magnar Hole; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; fysik; Physics;

    Sammanfattning : This thesis presents and discusses the results of measurements of the intrinsic lifetimes of bound excited anionic states. The results are valuable for evaluation of different theoretical models and computation methods and are compared to calculations when available. LÄS MER

  4. 3. Measurements of Oscillator Strengths in Fe, Zr, Mo and Ce

    Författare :Carl Martin Sikström; Fysiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; cerium; molybdenum; Atomic and molecular physics; Atom- och molekylärfysik; Condensed matter:electronic structure; magnetic and optical properties; electrical; magnetic resonance; supraconductors; relaxation; spectroscopy; Kondenserade materiens egenskaper:elektronstruktur; egenskaper elektriska; astrophysics; magnetiska och optiska ; spektroskopi; oscillator strengths; supraledare; zirconium; magnetisk resonans; Fourier transform spectroscopy; branching fraction; radiative lifetimes; iron;

    Sammanfattning : Atomic data are needed in many different areas of science and technology. Examples of users are the astronomical community and the lighting industry. In this work, the purpose of the projects has been to produce reliable atomic data needed to solve specific astrophysical problems. LÄS MER

  5. 4. Spectroscopy of Stable and Radioactive Negative Ions

    Författare :Annie Ringvall-Moberg; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Atomic Physics; ISOLDE; CERN; Electron Correlation; Electron Affinity; Photodetachment; Negative Ions; Anions; Radioisotopes; Laser Photodetachment Spectroscopy; Resonance Ionization; Neutral Particle Detection; Wigner Threshold Law; Molecular Dissociation; RFQcb; DESIREE; Radiative Lifetimes;

    Sammanfattning : Negative ions are unique quantum systems which are of fundamental interest within the field of atomic physics due to the importance of the electron correlation in their creation, stability, and existence. Properties of these ions, such as the electron affinity, i.e. LÄS MER

  7. 5. Development of Experimental Methods, Data Analysis and Standards in Atomic Spectroscopy

    Författare :Kasper Öberg; Astronomi - Genomgår omorganisation; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Atom- och molekylärfysik; Atomic and molecular physics; ytterbium; spectroscopy; radiative lifetimes; oscillator strengths; neon; line shapes; light sources; Fourier-transform spectroscopy; branching fractions; Stark effect; spectroscopic techniques; LIF; Atomic data;

    Sammanfattning : The focus of this work is on the experimental techniques and data analysis in atomic spectroscopy. Improved methods for the analysis of spectra and the determination of level energies are presented. Most of these are based on a rigorous statistical treatment of the spectroscopic data. LÄS MER