Sökning: "NATURAL SCIENCES Physics Astronomy and astrophysics Solar physics"

Visar resultat 1 - 5 av 28 avhandlingar innehållade orden NATURAL SCIENCES Physics Astronomy and astrophysics Solar physics.

1. 1. Theoretical Atomic Spectroscopy of Earthbound and Stellar Plasma

   Författare :Jon Grumer; Matematisk fysik; []
   Nyckelord :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;

   Sammanfattning : 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. LÄS MER

3. 2. Thermophysical Modelling and Mechanical Stability of Cometary Nuclei

   Författare :Björn Davidsson; Dina Prialnik; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astronomy; Comets; Tidal physics; Light scattering; Radiative transfer; Thermophysics; Gas kinetics; Non-gravitational forces; Astronomi; Astronomy and astrophysics; Astronomi och astrofysik; Theoretical Astrophysics; teoretisk astrofysik;

   Sammanfattning : Comets are the most primordial and least evolved bodies in the Solar System. As such, they are unique sources of information regarding the early history of the Solar System. However, little is known about cometary nuclei since they are very difficult to observe due to the obscuring coma. LÄS MER

4. 3. Experimental and Computational Atomic Spectroscopy for Astrophysics : Oscillator strengths and lifetimes for Mg I, Si I, Si II, Sc I, and Sc II

   Författare :Asli Pehlivan Rhodin; Astronomi - Genomgår omorganisation; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Atomic Data; Astrophysics - Solar and Stellar Astrophysics;

   Sammanfattning : Atomic data such as oscillator strengths and wavelengths are important for astrophysical applications as they have a crucial role in determining abundances of specific elements in a star, a galaxy, or any object emitting radiation in the space. Stars in the Galaxy mostly keep the composition of the interstellar gas from which they were formed, therefore studying stellar abundances helps us understand how the Milky Way was formed and how it evolved. LÄS MER

5. 4. Origin of solar surface activity and sunspots

   Författare :Sarah Jabbari; Axel Brandenburg; Laurene Jouve; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Magneto-hydrodynamics; solar physics; dynamo theory; Astronomy; astronomi;

   Sammanfattning : Sunspots and active regions are two of the many manifestations of the solar magnetic field. This field plays an important role in causing phenomena such as coronal mass ejections, flares, and coronal heating. Therefore, it is important to study the origin of sunspots and active regions and determine the underlying mechanism which creates them. LÄS MER

7. 5. Thermal physics of asteroids

   Författare :Johan S. V. Lagerros; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astronomy; asteroids; infrared emission; thermophysical models; Astronomi; Astronomy and astrophysics; Astronomi och astrofysik; astronomi; Astronomy;

   Sammanfattning : The thermal infrared and microwave emission from asteroids have many applications. Fundamental physical properties can be investigated, which have implications for the geophysical evolution of the asteroids, and the early history of the solar system.A new thermophysical model of asteroids is presented. LÄS MER