Search for dissertations about: "Radio astronomy"

Showing result 16 - 20 of 116 swedish dissertations containing the words Radio astronomy.

  2. 16. The Extremes of Neutrino Astronomy : From Fermi Bubbles with IceCube to Ice Studies with ARIANNA

    Author : Elisabeth Unger; Allan Hallgren; Olga Botner; Antonio Capone; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; astroparticle physics; neutrino telescopes; IceCube; Fermi bubbles; ARIANNA; horizontal propagation; surface wave propagation; Fysik med inriktning mot elementarpartikelfysik; Physics with specialization in Elementary Particle Physics; High Energy Physics; Högenergifysik;

    Abstract : The Fermi bubbles are extended regions of hard gamma-ray emission which were discovered with Fermi-LAT data to exist above and below the Galactic Center. In order to explain the origin of the gamma-rays, different theories are proposed. READ MORE

  4. 17. Active Galactic Nuclei in galaxy surveys : Empirical paths to the fiery hearts of cosmic beasts

    Author : Beatriz Villarroel; Andreas J. Korn; Takis Konstantopoulos; Moshe Elitzur; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Astronomy; Astronomi;

    Abstract : Some galaxies emit excessive amounts of light from their centers, caused by accretion of gas onto super-massive black holes (SMBH). These galactic cores are often referred to as Active Galactic Nuclei (AGN) and they come in many different forms, distinguishable by their emission properties. READ MORE

  5. 18. Molecules and Dust around AGB stars : Mass-loss rates and molecular abundances

    Author : Sofia Ramstedt; Hans Olofsson; Fredrik Schöier; José Cernicharo; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; AGB stars; mass-loss; circumstellar abundances; Formation and development of stars; Stjärnors bildning och utveckling; Astronomy; astronomi;

    Abstract : All stars with a stellar mass of about 0.8–8 MSun will end their lives as asymptotic giant branch (AGB) stars. Through their extensive mass loss the AGB stars constitutes an important source of nuclear processed material. READ MORE

  6. 19. Dynamics of the interstellar matter in galaxies : isolated barred spiral galaxies : cloud formation processes

    Author : Kristen Helmuth; John Beckman; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Astronomy; Astronomi; Astronomy; astronomi;

    Abstract : The dynamical components of six isolated barred spiral (SB) galaxies are investigated. No evidence is found supporting the hypothesis of a low amount of dark matter being characteristic of SB galaxies. The presence of companion galaxies is found to correlate with an increased statistical spread in the neutral hydrogen (HI) extent. READ MORE

  7. 20. Constraints on the gas temperature in the solaratmosphere from multiwavelength inversions

    Author : João Manuel da Silva Santos; Jaime de la Cruz Rodríguez; Andreas Korn; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Sun; chromosphere; ALMA; inversions; Astronomy; astronomi;

    Abstract : In this Licentiate thesis I review the properties of the solar atmosphere and the diagnostic value ofdifferent spectral lines in the visible and ultraviolet (UV) along with the millimeter (mm) continua in theelectromagnetic spectrum of the Sun.While the solar atmosphere has been routinely observed in high-resolution from ground-based opti-cal telescopes such as the Swedish Solar Telescope (SST), and more recently in the UV from space tele-scopes such as the Interface Region Imaging Spectrograph (IRIS), radio observations lag behind despitetheir great usefulness. READ MORE