Sökning: "radiative lifetimes"
Visar resultat 1 - 5 av 22 avhandlingar innehållade orden radiative lifetimes.
1. Radiative Properties of Rare Earth Elements - Free and Bound in Crystals
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
2. Radiative lifetimes of bound excited states in anions : Measurements on long-lived metastable states in atomic anions
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
3. Measurements of Oscillator Strengths in Fe, Zr, Mo and Ce
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
4. Spectroscopy of Stable and Radioactive Negative Ions
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
5. Development of Experimental Methods, Data Analysis and Standards in Atomic Spectroscopy
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