Sökning: "Henning Zettergren"
Visar resultat 1 - 5 av 13 avhandlingar innehållade orden Henning Zettergren.
Sammanfattning : This thesis presents instrumentation developments and measurements performed at the Double ElectroStatic Ion Ring ExpEriment, DESIREE, at Stockholm University. DESIREE operates at cryogenic temperatures ~13 K, with very low background pressures of ~10-14mbar, allowing the observation of stored ions to long times of tens of seconds and longer. LÄS MER
2. Collision Induced Fragmentation of Molecules and Molecular Clusters : Knockout Driven Reactions in Fullerenes and PAHs
Sammanfattning : This licentiate thesis covers experimental and theoretical studies of the fragmentation and sub- sequent reactions of fullerenes or Polycyclic Aromatic Hydrocarbons (PAHs). I present results from experiments where atoms or ions collide with fullerenes, PAHs, or clusters of these mole- cules at energies from 100 eV up to tens of keV. LÄS MER
Sammanfattning : When molecules are excited by photons or energetic particles, they will cool through the emission of photons, electrons, or by fragmenting. Such processes are often thermal as they occur after the excitation energy has been redistributed across all degrees-of-freedom in the system. LÄS MER
4. Ionization and Fragmentation of Complex Molecules and Clusters : Biomolecules and Polycyclic Aromatic Hydrocarbons
Sammanfattning : This work deals with ionization and fragmentation of biomolecules and polycyclic aromatic hydrocarbon (PAH) molecules. They are studied in the gas phase both as isolated molecules and as weakly bound clusters. LÄS MER
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