Sökning: "Cosmic Radiation"

Visar resultat 6 - 10 av 44 avhandlingar innehållade orden Cosmic Radiation.

  1. 6. On the Escape of Lyman Radiation from Local Galaxies

    Författare :Elisabet Leitet; Nils Bergvall; Erik Zackrisson; Bengt Gustafsson; Duilia F. De Mello; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Galaxies; starbursts; spiral galaxies; Lyman continuum; Lyman alpha; leakage; cosmic reionization; escape fraction; Astronomy; Astronomi;

    Sammanfattning : Cosmic reionization was most likely initiated by star forming dwarf galaxies. Little is known about the physical mechanisms allowing ionizing Lyman continuum (LyC) photons to escape from galaxies, but to learn more we can study local galaxies in detail. LÄS MER

  3. 7. Cosmic clues from astrophysical particles

    Författare :Francesca Capel; Christer Fuglesang; Michael Unger; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fysik; Physics;

    Sammanfattning : Ultra-high-energy cosmic rays (UHECRs) are charged particles that have been accelerated to extreme energies, such that they are effectively travelling at the speed of light. Interactions of these particles with the Earth’s atmosphere lead to the development of extensive showers of particles and radiation that can be measured with existing technology. LÄS MER

  4. 8. Cosmic dust and heavy neutrinos

    Författare :Erik Elfgren; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fysik; Fysik;

    Sammanfattning : This Doctoral thesis treats two subjects. The first subject is the impact of early dust on the cosmic microwave background (CMB). The dust that is studied comes from the first generation of stars, which were hot and short-lived, ending their lives as giant supernovae. LÄS MER

  5. 9. Modeling Quantum Cascade Lasers : The Challenge of Infra-Red Devices

    Författare :Martin Franckie; Matematisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Quantum Cascade Lasers; Non-equilibrium Green s functions; Modeling; semiconductor heterostructures; Quantum Cascade Lasers; Non-equilibrium Green s functions; THz radiation; infrared radiation; semiconductor heterostructures; Modeling Simulation Technology; Fysicumarkivet A:2016:Franckié;

    Sammanfattning : We live in a time of rapid scientific and technological advancement. People liv- ing 100 years ago could never dream of inventions like those having completely changed our way of life, and our perception of the world; computers, mobile phones, the Internet, space travel, unraveling the mysteries of the early universe and distant galaxies, and our insight into the microscopic world of quantum phe- nomena. LÄS MER

  7. 10. GLAST CsI(Tl) Crystals

    Författare :Sara Bergenius; KTH; []
    Nyckelord :GLAST; radiation damage; CsI Tl ; calorimetry; cosmic rays;

    Sammanfattning : .... LÄS MER