Search for dissertations about: "momentum imaging"

Showing result 1 - 5 of 24 swedish dissertations containing the words momentum imaging.

  1. 1. Ultrafast Photoionization Dynamics Studied with Coincidence Momentum Imaging Spectrometers

    Author : Yu-Chen Cheng; Atomfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; 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;

    Abstract : 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. READ MORE

  2. 2. Isomeric yield ratio measurements with JYFLTRAP : In quest of the angular momentum of the primary fragments

    Author : Vasileios Rakopoulos; Mattias Lantz; Stephan Pomp; Andreas Solders; José Benlliure; Uppsala universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Nuclear physics; nuclear fission; angular momentum; fission fragments; isomeric yield ratios; fission products; scission; Penning trap.; Physics with specialization in Nuclear Physics; Fysik med inriktning mot kärnfysik;

    Abstract : 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. READ MORE

  3. 3. Dissociation dynamics of highly excited molecules: Theory and Experiment

    Author : Shabnam Oghbaie; Synkrotronljusfysik; []
    Keywords : Molecular dissociation; core-electron excitation; double ionization; femtoseconds molecular dynamics; Isomerization; symmetry breaking; momentum imaging; site-selective dissociation; butadiene; cyclopropane; nuclear dynamics; Auger decay;

    Abstract : 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. READ MORE

  4. 4. Ultra-fast dynamics in atoms and molecules during photoionization: from attoseconds to femtoseconds

    Author : Erik Månsson; Synkrotronljusfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; photoelectron spectroscopy; momentum imaging; coincident detection; correlation; direct double ionization; Born–Oppenheimer approximation; high harmonics; synchrotron radiation; Fysicumarkivet A:2014:Månsson;

    Abstract : 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. READ MORE

  5. 5. Particle dynamics during biomass devolatilization : Momentum exchange and particle dispersion

    Author : Angel David Garcia Llamas; Kentaro Umeki; Rikard Gebart; Per Gren; Peter Glarborg; Luleå tekniska universitet; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Biomass; devolatilization; rocketing; PIV; PTV; Energiteknik; Energy Engineering;

    Abstract : 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. READ MORE