Sökning: "NATURVETENSKAP Fysik Atom- och molekylfysik Atomfysik"

Visar resultat 1 - 5 av 132 avhandlingar innehållade orden NATURVETENSKAP Fysik Atom- och molekylfysik Atomfysik.

  1. 1. Feature Extraction for Low-Frequency Signal Classification

    Författare :José Chilo; Thomas Lindblad; Christian Bohm; KTH; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; infrasound; seismic signals; feature extraction; wavelets; fingerprints; mining; multimodal data space; Atomic physics; Atomfysik; Infrasound; data acquisition; Electronics; Elektronik;

    Sammanfattning : The development of the International Monitoring System (IMS) for the verification of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) has led to a rapid revival of interest in infrasound. Furthermore, the installation of low-frequency sensors at seismic sites has increased in recent years, providing researchers with large and heterogeneous data-sets in near real-time. LÄS MER

  2. 2. Resonant States in Negative Ions

    Författare :Nicklas Brandefelt; John S. Briggs; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Molekylfysik; Atomfysik; Kärnfysik; Partikelfysik; Atomic and molecular physics; Atom- och molekylfysik;

    Sammanfattning : Resonant states are multiply excited states in atoms and ions that have enough energy to decay by emitting an electron. The ability to emit an electron and the strong electron correlation (which is extra strong in negative ions) makes these states both interesting and challenging from a theoretical point of view. LÄS MER

  3. 3. Guiding of highly charged ions through insulating nanocapillaries

    Författare :Hongqiang Zhang; Reinhold Schuch; Amine Cassimi; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; Physics; Fysik; Atomic physics; Atomfysik; fysik; Physics;

    Sammanfattning : This thesis contains experimental work on guiding of highly charged ions through insulating nanocapillaries. We have studied the time evolution of angular distributions of transmitted ions under well defined initial conditions: already charged, as well as fully discharged nanocapillaries, by using a two-dimensional position sensitive Micro Channel Plate detector with a data acquisition system working in event mode. LÄS MER

  4. 4. Extreme Electron Beams and Brilliant X-rays : Generation, Manipulation and Characterization of Relativistic Electron Beams for and from Plasma-Based Accelerators

    Författare :Jonas Björklund Svensson; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; laser; plasma; wakefield; acceleration; accelerator; relativistic; electrons; x-rays; ultra-fast; betatron; laser-wakefield acceleration; plasma-wakefield acceleration; Fysicumarkivet A:2020:Björklund;

    Sammanfattning : This thesis is based on work done by the author on the development of plasma-based electron accelerators driven by ultra-intense laser pulses and dense electron bunches. Plasma based accelerators have several benefits, such as accelerating fields around 1000 times stronger than in “conventional” radio-frequency accelerators, which can allow for shrinking the overall footprint of the accelerator. LÄS MER

  5. 5. Detector Development, Source Characterization and Novel Applications of Laser Ion Acceleration

    Författare :Lovisa Senje; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Laser; Ion; Acceleration; Proton; Water; Sheath; Lifetime; Laser; Ion; Acceleration; Proton; Water; Radiolysis; Sheath; Detector; Fysicumarkivet A:2017:Senje;

    Sammanfattning : The main focus of the work presented in this thesis is on experimental studies oflaser acceleration of protons and other positive ions from solid targets. The topic is explored from three different angles: firstly, the development of diagnostics adapted to the ion pulses, secondly, the characterization of the source of the energetic particles and, finally, the application of laser-accelerated protons for time-resolved radiolysis of glass and water. LÄS MER