Sökning: "cosmic rays"

Visar resultat 1 - 5 av 52 avhandlingar innehållade orden cosmic rays.

  1. 1. Searching for Gamma Rays from Galaxy Clusters with the Fermi Large Area Telescope : Cosmic Rays and Dark Matter

    Författare :Stephan Zimmer; Jan Conrad; Christophe Clement; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; galaxy clusters; gamma rays; cosmic rays; dark matter; fermi-lat; likelihood analysis; joint likelihood;

    Sammanfattning : In this licentiate thesis, I report a search for GeV γ rays towards the location of Galaxy clusters. I mainly discuss the results of a search for cosmic-ray (CR) induced γ-ray emission but also briefly elaborate on a related study, searching for Dark Matter (DM)-induced γ-ray emission from Galaxy clusters. LÄS MER

  2. 2. Gamma-Ray Emission from Galaxy Clusters : DARK MATTER AND COSMIC-RAYS

    Författare :Anders Pinzke; Lars Bergström; Olaf Reimer; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Galaxy clusters; gamma-rays; cosmic-rays; dark matter; High energy astrophysics; Högenergiastrofysik; Theoretical Physics; teoretisk fysik;

    Sammanfattning : The quest for the first detection of a galaxy cluster in the high energy gamma-ray regime is ongoing, and even though clusters are observed in several other wave-bands, there is still no firm detection in gamma-rays. To complement the observational efforts we estimate the gamma-ray contributions from both annihilating dark matter and cosmic-ray (CR) proton as well as CR electron induced emission. LÄS MER

  3. 3. Observations of nearby Galaxy Clusters with the Fermi Large Area Telescope : Towards the first Gamma Rays from Clusters

    Författare :Stephan Zimmer; Jan Conrad; Lars Bergström; Torsten Enßlin; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Galaxy Clusters; Fermi-LAT; γ rays; Dark Matter; Cosmic Rays; Physics; fysik;

    Sammanfattning : Galaxy clusters are the most massive bound systems known in the Universe and are believed to have formed through large scale structure formation. They host relativistic cosmic-ray (CR) populations and are gravitationally bound by large amounts of Dark Matter (DM), both providing conditions in which high-energy gamma rays may be produced either via CR interactions with the intracluster medium or through the annihilation or decay of DM particles. LÄS MER

  4. 4. Atmospheric and Interstellar Cosmic Rays Measured With the CAPRICE98 Experiment

    Författare :Emiliano Mocchiutti; KTH; []
    Nyckelord :Cosmic rays; balloons; atmospheric measurements; interstellar spectrum; superconducting magnet; RICH detector;

    Sammanfattning : .... LÄS MER

  5. 5. Studies of cosmic rays with the anticoincidence system of the PAMELA satellite experiment

    Författare :Silvio Orsi; Mark Pearce; Martin Pohl; KTH; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; astrophysics; astroparticle physics; antimatter; organic scintillators; cosmic rays; trapped particles; Astroparticle physics; Astropartikelfysik;

    Sammanfattning : PAMELA is a satellite-borne experiment designed to study the charged component of the cosmic radiation of galactic, solar and trapped nature. The main scientific objective is the study of the antimatter component of cosmic rays over a wide range of energies (antiprotons: 80 MeV–190 GeV, positrons: 50 MeV–270 GeV). LÄS MER