Sökning: "Ionization Dynamics"

Visar resultat 16 - 20 av 75 avhandlingar innehållade orden Ionization Dynamics.

1. 16. Soft X-ray Scattering Dynamics Close to Core Ionization Thresholds in Atoms and Molecules

   Författare :Johan Söderström; Jan-Erik Rubensson; Lorenzo Avaldi; Uppsala universitet; []
   Nyckelord :Physics; Soft X-ray emission; Resonant inelastic X-ray scattering; Double excitations; Helium; X-ray-emission-threshold-electron coincidence; Fysik;

   Sammanfattning : In this Thesis studies of highly excited states in gas-phase atoms and molecules (He, Ne, N2, O2, N2O and CO2) using a variety of synchrotron-radiation based techniques are presented. The three techniques used most frequently are X-ray-emission-threshold-electron coincidence (XETECO), X-ray emission spectroscopy (XES) and X-ray photoelectron spectroscopy (XPS) and they are all given a brief introduction. LÄS MER

3. 17. Non-Linear Spatio-Temporal Dynamics of Optical Beams and Pulses in Kerr and Ionizable Media

   Författare :Manuel López Quiroga Teixeiro; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; self-focussing; wave-breaking; optical Kerr effect; autowaves; fast adiabatic compression; non-linear modes conversion; non-linear optics; blue-shift; solitons; full wave numerical simulations; optical fibers; ionization non-linearities; pulse compressioni;

   Sammanfattning : The present thesis includes results of several investigations concerning the propagation of optical pulses in optical fibers and spatio-temporal beams in optical Kerr media and ionizable media. Both numerical and analytical methods play an important role in the investigations. LÄS MER

4. 18. Ultrafast Spectroscopy of Atomic and Molecular Quantum Dynamics

   Författare :Pia Johansson; Tony Hansson; Bertrand Girard; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chemical physics; Kemisk fysik;

   Sammanfattning : An all-pervading feature of the work presented in this thesis is the study of ultrafast dynamics, both theoretically and experimentally, in terms of time-dependent wave functions (wave packets).We have experimentally, by pump-probe fluorescence spectroscopy, examined spin-orbit interactions, by time-tracing molecular wave packets on excited states of diatomic rubidium, and the main channels causing the fast predissociation from one of those states is revealed. LÄS MER

5. 19. Electronic Structure and Core-Hole Dynamics of Ozone : Synchrotron-radiation based studies and ab-initio calculations

   Författare :Karoline Wiesner; Svante Svensson; Olle Björneholm; Robert E. Continetti; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik; Physics; Fysik;

   Sammanfattning : The electronic structure of the ozone molecule O3 has been studied with spectroscopy techniques and computations. The investigation was focused on O3 in a core-hole state. The electronic configuration and the nuclear dynamics have been found to be highly correlated. LÄS MER

7. 20. Ultrafast Photoionization Dynamics Studied with Coincidence Momentum Imaging Spectrometers

   Författare :Yu-Chen Cheng; Atomfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Photoionization; High-order Harmonic Generation; Extreme Ultraviolet; Free-Electron Laser; Molecular Dissociation; Charge Transfer; Coincidence Measurement; Momentum Imaging; Electron Wave Packet; Fysicumarkivet A:2019:Cheng;

   Sammanfattning : The time scale of the dynamics in atoms and molecules varies from attoseconds (10-18) to picoseconds (10-12) depending on the size of the particles. To study such dynamics, ultrafast light pulses are needed to trigger and capture the reaction. One of the most direct methods consists in ionizing the system and observing the following response. LÄS MER