Search for dissertations about: "gamma-ray"
Showing result 1 - 5 of 97 swedish dissertations containing the word gamma-ray.
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1. Photospheric emission in gamma ray bursts : Analysis and interpretation of observations made by the Fermi gamma ray space telescope
Abstract : The large flashes of radiation that are observed in GRBs are generally believed to arise in a relativistic jetted outflow. This thesis addresses the question of how and where in the jet this radiation is produced. READ MORE
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2. Multi-messenger emission from gamma-ray bursts
Abstract : Multi-messenger astronomy is a very hot topic in the astrophysical community. A messenger is something that carries information. Different astrophysical messenger types are photons, cosmic rays, neutrinos, and gravitational waves. They all carry unique and complementary information to one another. READ MORE
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3. Microphysical Conditioning of Gamma-Ray Burst Shocks
Abstract : Gamma-Ray Bursts (GRBs) are believed to be connected with either collapse of massive stars or – in some cases – coalescing neutron stars, both of which cause extreme relativistic explosions observable from the entire Universe. GRBs produce rapid flashes of high energy radiation, extending up to 2MeV in photon energies: as much energy per photon as the rest mass of 4 electrons. READ MORE
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4. Cosmological Dark Matter and the Isotropic Gamma-Ray Background : Measurements and Upper Limits
Abstract : This thesis addresses the isotropic diffuse gamma-ray background, as measured by the Fermi gamma ray space telescope, and its implications for indirect detection of dark matter. We describe the measurement of the isotropic background, including also an alternative analysis method besides the one published by the Fermi-LAT collaboration. READ MORE
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5. PoGOLite : The Polarised Gamma-ray Observer
Abstract : PoGOLite is a balloon-borne experiment which will study polarised soft gamma-ray emission from astrophysical targets in the 25 keV – 80 keV energy range by applying well-type phoswich detector technology. Polarised gamma-rays are expected from a wide variety of sources including rotation-powered pulsars, accreting black holes and neutron stars, and jet-dominated active galaxies. READ MORE