Search for dissertations about: "Cygnus"

Found 4 swedish dissertations containing the word Cygnus.

  2. 1. Waterfowl herbivory on submerged macrophytes in eutrophic lakes

    Author : Håkan Sandsten; Biologiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; limnology; Marinbiologi; limnologi; Hydrobiology; Växtekologi; Plant ecology; akvatisk ekologi; Djurekologi; Animal ecology; Anas; Fulica atra; Cygnus; alternative stable states; water depth; distribution; plant species composition; hydrophytes; propagule size; Herbivory; tuber; Potamogeton; marine biology; aquatic ecology;

    Abstract : Submerged macrophytes are thought to stabilize clear-water states of shallow lakes. The aim of this thesis was to elucidate how waterfowl herbivory can affect abundance, distribution and species composition of submerged macrophytes in eutrophic lakes. READ MORE

  4. 2. Measurements of hard X-ray polarization from the Crab and Cygnus X-1

    Author : Victor Mikhalev; Mark Pearce; Herman Marshall; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Fysik; Physics; Fysik; Physics;

    Abstract : Polarimetry provides insights into the emission mechanisms of astrophysical sources by elucidating their magnetic field and geometry. Hard X-rays are produced in \mbox{regions} with strong magnetic fields or strong gravitational effects, which makes them a probe of extreme environments. READ MORE

  5. 3. X-ray variability in Galactic high-mass black hole binaries

    Author : Magnus Axelsson; Stefan Larsson; Chris Done; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Accretion; high-energy astrophysics; temporal variability; X-ray binaries; Astronomy and astrophysics; Astronomi och astrofysik; Astronomy; astronomi;

    Abstract : The stars of the night sky can to the naked eye appear to be steady and unchanging, apart from the twinkling created by air moving in the atmosphere. However, when viewed in X-rays, the sky is far from constant, with detectable changes occurring on very short timescales.Black hole X-ray binaries are strong sources of X-rays. READ MORE

  6. 4. Pre-Flight Development of the PoGOLite Pathfinder

    Author : Mózsi Kiss; Mark Pearce; Gottfried Kanbach; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Astroparticle physics; Astropartikelfysik;

    Abstract : The Polarized Gamma-ray Observer (PoGOLite) is a balloon-borne instrument that will measure gamma-ray polarization in the energy range 25-80 keV from astronomical sources such as pulsars, accretion discs and jets from active galacticnuclei. The two additional parameters provided by such observations, polarizationangle and degree, will allow these objects to be studied in a new way, providing information about their emission mechanisms and geometries. READ MORE