Sökning: "Secondary electron cascades"

Hittade 5 avhandlingar innehållade orden Secondary electron cascades.

  1. 1. Towards Single Molecule Imaging - Understanding Structural Transitions Using Ultrafast X-ray Sources and Computer Simulations

    Författare :Carl Caleman; Janos Hajdu; Richard Neutze; Uppsala universitet; []
    Nyckelord :Molecular biophysics; XFEL; Ultrafast Melting; InSb; Molecular Dynamics; Water Cluster; Evaporation; Secondary Electron; Photo-cathode; Electron Scattering; Energy Loss Function; Single Particle Imaging; X-ray Diffraction; Water; Ice; KI; CsI; Molekylär biofysik;

    Sammanfattning : X-ray lasers bring us into a new world in photon science by delivering extraordinarily intense beams of x-rays in very short bursts that can be more than ten billion times brighter than pulses from other x-ray sources. These lasers find applications in sciences ranging from astrophysics to structural biology, and could allow us to obtain images of single macromolecules when these are injected into the x-ray beam. LÄS MER

  2. 2. Towards ultrafast imaging with extreme ultraviolet light sources

    Författare :Jörg Schwenke; Lunds universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Photo emission electron microscopy; Focusing of X-ray radiation; Digital holography; High-order harmonic generation; Free-electron laser seeding; Secondary electron cascades; Fysicumarkivet A:2012:Schwenke;

    Sammanfattning : This thesis reports experimental studies performed with two advanced coherent XUV sources with ultrashort pulse duration, high-order harmonic generation and seeded-free electron laser. High-order harmonic generation (HHG) is the generation of overtones of a fundamental laser pulse in a medium, e.g. noble gases. LÄS MER

  3. 3. First Principles Calculations of Electron Transport and Structural Damage by Intense Irradiation

    Författare :Carlos Ortiz; Olle Eriksson; Mattias Klintenberg; Richard A. London; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Condense matter theory; electronic structure; quasiparticles; GW theory; molecular dynamics; Boltzmann transport; electron transport; impact ionization; structural damage; dielectric response; structural biology; radiation detectors; scintillators; positron emission tommography; Electronic structure; Elektronstruktur; Semiconductor physics; Halvledarfysik; Biological physics; Biologisk fysik; Critical phenomena phase transitions ; Kritiska fenomen fasövergångar ; Functional materials; Funktionella material; Materiefysik; Physics of Matter;

    Sammanfattning : First principle electronic structure theory is used to describe the effect of crystal binding on radiation detectors, electron transport properties, and structural damage induced by intense irradiation. A large database containing general electronic structure results to which data mining algorithms can be applied in the search for new functional materials, a case study is presented for scintillator detector materials. LÄS MER

  4. 4. Beyond scattering – what more can be learned from pulsed keV ion beams?

    Författare :Svenja Lohmann; Daniel Primetzhofer; Andreas Wucher; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Charge exchange; Deep UV photons; Electron emission; Silicon; Sputtering; TOF-MEIS; Fysik; Physics;

    Sammanfattning : Interactions of energetic ions with matter govern processes as diverse as the influence of solar wind, hadron therapy for cancer treatment and plasma-wall interactions in fusion devices, and are used for controlled manipulation of materials properties as well as analytical methods. The scattering of ions from target nuclei and electrons does not only lead to energy deposition, but can induce the emission of different secondary particles including electrons, photons, sputtered target ions and neutrals as well as nuclear reaction products. LÄS MER

  5. 5. Electronic excitation, luminescence and particle emission : Studying ion-induced phenomena in ToF-MEIS

    Författare :Svenja Lohmann; Daniel Primetzhofer; Friedrich Aumayr; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TOF-MEIS; ion beam analysis; deep UV; desorption; electronic sputtering; TiN;

    Sammanfattning : Medium energy ion scattering (MEIS) is an experimental technique for the high-resolution depth profiling of thin films. Commonly, ions with energies between several ten to a few hundred keV are employed as probes, and backscattered particles are detected. LÄS MER