Search for dissertations about: "NATURAL SCIENCES Physics Other physics Statistical physics"

Showing result 16 - 20 of 215 swedish dissertations containing the words NATURAL SCIENCES Physics Other physics Statistical physics.

  2. 16. Modelling of laser plasma interaction with applications to particle acceleration and radiation generation

    Author : Benjamin Svedung Wettervik; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; plasma; ion acceleration; continuum methods; electron wakefield acceleration; raditation generation; coherent X-ray pulses; Vlasov-Maxwell equations;

    Abstract : The development of laser systems with ultra-high intensities has allowed the study of the relativistic interaction of laser light and ionized matter, plasmas, as well as opened up prospects for compact particle accelerators, generation of high intensity X-ray, XUV radiation, and probing QED-effects, which are present in the high intensity regime. To describe laser matter interaction, it is necessary to self-consistently account for the paths of a large number of particles and the corresponding electromagnetic fields, with the addition of stochastic effects at high laser intensities. READ MORE

  4. 17. Isospin Breaking in Kaon Decays to Pions

    Author : Fredrik Borg; Teoretisk partikelfysik - Geonomgår omorganisation; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Elementary particle physics; termodynamik; statistisk fysik; gravitation; relativitet; kvantmekanik; thermodynamics; Matematisk och allmän teoretisk fysik; Pseudo-scalar meson; Isospin Breaking; Chiral Perturbation Theory; Mathematical and general theoretical physics; classical mechanics; quantum mechanics; relativity; statistical physics; Weak Interaction; Strong Interaction; kvantfältteori; High energy interactions; Kärnfysik; Nuclear physics; klassisk mekanik; quantum field theory; cosmic rays; Kosmisk strålning; högenergi; Elementarpartikelfysik;

    Abstract : The five different K -> 3 Pi and the three K -> 2 Pi decays are calculated in Chiral Perturbation Theory. The calculation is done using different approximations, to study whether this changes the result significantly. First the isospin approximation is used. Discrepancies are then found between theory and experiment. READ MORE

  5. 18. A Serendipitous Journey through Stochastic Processes

    Author : Ludovico Theo Giorgini; John S Wettlaufer; Valerio Lucarini; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Stochastic process; statistical physics; machine learning; Theoretical Physics; teoretisk fysik;

    Abstract : In this PhD thesis we will present some new insights in different problems in the field of stochastic processes. A stochastic resonance system is studied using path integral techniques, originally developed in quantum field theory, to recover the optimal means through which noise self-organises before a rare transition from one potential well to the other. READ MORE

  6. 19. Radiation Oncology Data and Modelling Side Effects after Radiation Therapy

    Author : Caroline Olsson; Göteborgs universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; dose and side effect data; dose-volume response; fractionation effect; LQ model; sequential two-phase radiotherapy; head and neck cancer; parotid gland; xerostomia; pelvic radiotherapy; gynecological cancer; pubic bone; pain; data integration; xerostomia;

    Abstract : Although modern radiation therapy techniques have the ability to conform the dose distribution of ionizing radiation tightly around the volume to be treated, unwanted irradiation to surrounding organs remains a problem. The probability of a side effect arising in the normal tissue of a patient after radiation therapy can be modelled by sigmoid mathematical functions known as normal tissue complication probability (NTCP) models. READ MORE

  7. 20. Statistical processing of Flash X-ray Imaging of protein complexes

    Author : Alberto Pietrini; Carl Nettelblad; Johan Bielecki; Janos Hajdu; Flavio Capotondi; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; X-ray; XFEL; single particle; hit-finder; statistical hit-finder; single protein; protein complex; RNA polymerase II; FEL; free-electron laser; FXI; Flash X-ray Imaging; CXI; CSPAD; x-ray imaging; COACS; Physics with specialization in Biophysics; Fysik med inriktning mot biofysik;

    Abstract : Flash X-ray Imaging (FXI) at X-ray Free Electron Lasers (XFELs) is a promising technique that permits the investigation of the 3D structure of molecules without the need for crystallization, by diffracting on single individual sample particles.In the past few years, some success has been achieved by using FXI on quite large biological complexes (40 nm-1 μm in diameter size). READ MORE