Search for dissertations about: "NATURVETENSKAP Fysik Astronomi och astrofysik"

Showing result 6 - 10 of 460 swedish dissertations containing the words NATURVETENSKAP Fysik Astronomi och astrofysik.

  2. 6. Magnetic fields around massive protostars as traced by masers and dust emission

    Author : Daria Dall` Olio; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; magnetic field – stars: formation – stars: massive – masers – dust – polarization – stars: individual: IRAS 18089-1732 – G9.62 0.19;

    Abstract : It is not fully clear how the magnetic field acts during the first stages of star formation. A possible way to clarify its role is to observe the polarized light coming from masers and thermal dust emission. READ MORE

  4. 7. Gravitational perturbations in plasmas and cosmology

    Author : Mats Forsberg; Gert Brodin; Michael Bradley; Christopher Clarkson; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; general relativity; cosmology; gravitational waves; plasma; electromagnetic waves; nonlinear waves; Plasma physics; Plasmafysik; Theory of relativity; gravitation; Relativitetsteori; gravitation; Cosmology; Kosmologi; teoretisk fysik; Theoretical Physics;

    Abstract : Gravitational perturbations can be in the form of scalars, vectors or tensors. This thesis focuses on the evolution of scalar perturbations in cosmology, and interactions between tensor perturbations, in the form of gravitational waves, and plasma waves. READ MORE

  5. 8. Regolith Properties of Mercury Derived from Observations and Modelling

    Author : Johan Warell; Nick Thomas; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Astronomy; Mercury; Moon; imaging; photometry; spectroscopy; regolith; space weathering; light scattering; spectral modelling; Astronomi; Astronomy and astrophysics; Astronomi och astrofysik; astronomi; Astronomy;

    Abstract : The properties of Mercury's regolith have been investigated at optical and near-infrared wavelengths with high-resolution imaging, photometric, and spectroscopic observations with the Swedish Vacuum Solar Telescope and the Nordic Optical Telescope. A new global optical map at a spatial resolution of 200 km shows that the well known (from Mariner 10) and poorly known hemispheres are indistinguishable with respect to the distribution, number density, and morphological parameters of bright albedo features. READ MORE

  6. 9. Theoretical Atomic Spectroscopy of Earthbound and Stellar Plasma

    Author : Jon Grumer; Matematisk fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; atomstruktur; atomära processer; elektronkorrelation; plasmaspektroskopi; magnetfält; hyperfinstruktur; solkoronan; rymdväder; förekomst av grundämnen i stjärnor; datorsimuleringar; Zeemaneffekt; relativistiska effekter; atomic structure; atomic processes; computer simulation; electron correlation; relativistic atomic theory; plasma spectroscopy; Zeeman effect; magnetic fields; hyperfine structure; solar corona; space weather; stellar abundances; Fysicumarkivet A:2016:Grumer;

    Abstract : Motivated by spectroscopic analysis of astrophysical and laboratory plasma, this thesis concerns the fundamental structure and spectral properties of atoms and their ions. The multiconfiguration Dirac-Hartree-Fock (MCDHF) method is used to predict the emission or absorption of radiation, by atomic systems in general, and of heavy and highly charged ions in particular. READ MORE

  7. 10. Arithmetic and Hyperbolic Structures in String Theory

    Author : Daniel Persson; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Instantons; Kac-Moody algebras; Spacelike singularities; String Theory;

    Abstract : This thesis consists of an introductory text followed by two separate parts which may be read independently of each other. In Part I we analyze certain hyperbolic structures arising when studying gravity in the vicinity of spacelike singularities (the BKL-limit). READ MORE