Sökning: "Synchrotron radiation"

Visar resultat 11 - 15 av 187 avhandlingar innehållade orden Synchrotron radiation.

1. 11. Gas phase molecular relaxation probed by synchrotron radiation experiments

   Författare :Jaume Rius i Riu; KTH; []
   Nyckelord :Molecular relaxation; synchrotron radiation; dispersed fluorescence; photoelectron spectroscopy; energy resolved electron ion coincidence technique;

   Sammanfattning : This thesis presents experimental studies of gas phasemolecular relaxation after excitation with synchrotron photonsin the 15-35 eV and in the 70-350 eV regions.In the 15-35 eV region, molecular relaxation by neutraldissociation processes and nonFranck-Condon effects in N2 and O2 molecules have beenstudied by means of dispersed fluorescence and photoelectronspectroscopy experimental techniques, respectively. LÄS MER

3. 12. Radiation in simulations of high intensity laser-matter interaction

   Författare :Erik Karl Wallstén Wallin; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; plasma; nonlinear dynamics; particle-in-cell; Manley-Rowe; radiation reaction; synchrotron radiation;

   Sammanfattning : We consider electromagnetic waves propagating in plasmas, with two main themes covered. First nonlinear plasma theory and wave-wave interaction. Here a wave-wave symmetry, the Manley-Rowe relations, is used as a method of determining the physicality of modified plasma fluid equations. LÄS MER

4. 13. Synchrotron Radiation, Adsorption Isotherms and the Large Hadron Collider Vacuum System

   Författare :Erik Wallén; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; H2; photon stimulated desorption; CO2; cryotrapping; liquid He; accelerators; isotherms; CH4; He; Monte Carlo simulations; synchrotron radiation; vacuum; CO; physisorption;

   Sammanfattning : In circular particle accelerators and storage rings with relativistic beams of particles, e.g. electrons or protons, the vacuum performance of the accelerator is determined by the outgassing from the walls of the beam vacuum chamber. LÄS MER

5. 14. Free Molecular and Metal Clusters Studied by Synchrotron Radiation Based Electron Spectroscopy

   Författare :Aldana Rosso; Svante Svensson; Olle Björneholm; Maxim Tchaplyguine; Gunnar Öhrwall; Uwe Hergenhahn; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; nanoparticles; free clusters; molecular clusters; metal clusters; photoelectron spectroscopy; synchrotron radiation; local structure; core level spectroscopy; auger spectroscopy; heterogeneous clusters; nucleation; bromomethane; chloromethane; benzene; bromobenzene; chlorobenzene; potassium; sodium; simple metals; Physics; Fysik;

   Sammanfattning : The main purpose of this Thesis is the experimental characterization of the electronic and geometric structures of objects called clusters. A cluster consists of a finite group of bound atoms or molecules. Due to its finite size, it may present completely different properties than those of the isolated atom and the bulk. LÄS MER

7. 15. Studies of Molecular and Cluster Fragmentation Using Synchrotron Radiation: Measurements and Models

   Författare :Andreas Lindgren; Synkrotronljusfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Atom- och molekylärfysik; Atomic and molecular physics; photoionization; synchrotron radiation; localized excitation; electron-ion coincidence; induced alignment; clusters; molecules; core excitation; mass spectroscopy; fragmentation; dissociation;

   Sammanfattning : A new spectrometer for studying photoinduced fragmentation has been designed and commissioned. The instrument produces a detailed view of the energy and angular emission of fragments, which in the case of small molecules can be related to their geometry at the moment of dissociation. LÄS MER