Sökning: "momentum imaging"
Visar resultat 1 - 5 av 26 avhandlingar innehållade orden momentum imaging.
1. Ultrafast Photoionization Dynamics Studied with Coincidence Momentum Imaging Spectrometers
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
2. Isomeric yield ratio measurements with JYFLTRAP : In quest of the angular momentum of the primary fragments
Sammanfattning : In this thesis, isomeric yield ratios of twenty nuclides produced in the fission of natU and 232Th by protons at 25-MeV and natU by high-energy neutrons were studied. The experiments were performed at the IGISOL-JYFLTRAP facility at the University of Jyväskylä. LÄS MER
3. Dissociation dynamics of highly excited molecules: Theory and Experiment
Sammanfattning : This thesis presents studies on dissociation of two model molecules: Butadiene and Cyclopropane. Tunable synchrotron radiation was used to ionize or excite the molecules in the gas phase, and the momentum correlation of the resulting fragment ions were measured using a 3D momenta coincident ion spectroscopy. LÄS MER
4. Ultra-fast dynamics in atoms and molecules during photoionization: from attoseconds to femtoseconds
Sammanfattning : Treating the correlated behaviour of multiple particles is challenging for both theory and experiment. This thesis reports on a variety of experimental investigations aiming to advance the understanding of fundamental processes in atoms and molecules: double ionization, isomerization and dissociation. LÄS MER
5. Particle dynamics during biomass devolatilization : Momentum exchange and particle dispersion
Sammanfattning : Devolatilization is a heat-driven thermochemical process in which a liquid or a solid fuel releases mass in the form of volatile compounds after drying, as a result of the combination of endothermic and exothermic reactions. It differs from pyrolysis in that it does not require an inert atmosphere and that the reactant must be either solid or liquid. LÄS MER
