Search for dissertations about: "Sun: corona"

Showing result 1 - 5 of 8 swedish dissertations containing the words Sun: corona.

  1. 1. Formation of solar bipolar regions Magnetic flux concentrations from suction of the negative effective magnetic pressure instability

    University dissertation from Stockholm : Department of Astronomy, Stockholm University

    Author : Illa Rivero Losada; Stockholms universitet.; [2018]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Magnetohydrodynamics MHD ; turbulence; dynamo; Sun: magnetic fields; Sun: rotation; Sun: activity; Sun: dynamo; Astronomy; astronomi;

    Abstract : Sunspots stand out on the visible solar surface. They appear as dark structures evolving and changing over time. They host energetic and violent events, like coronal mass ejections and flares, and concentrate strong magnetic fields. READ MORE

  2. 2. Radar Probing of the Sun

    University dissertation from Uppsala : Acta Universitatis Upsaliensis

    Author : Mykola Khotyaintsev; Uppsala universitet.; [2006]
    Keywords : Space and plasma physics; solar radar; active experiments; space physics; solar corona; plasma; Rymd- och plasmafysik;

    Abstract : This thesis is dedicated to the theory of solar radar experiments. The Sun exhibits a variety of interesting and complicated physical phenomena, examined mainly through analysis of its radiation. Active solar probing by radar provides an alternative possibility to study the Sun. READ MORE

  3. 3. Solitary waves and enhanced incoherent scatter ion lines

    University dissertation from Kiruna : Institutet för rymdfysik, Umeå universitet

    Author : Jonas Ekeberg; Umeå universitet.; [2011]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; plasma waves and instabilities; nonlinear phenomena; solitons and solitary waves; ionosphere; Sun: corona; incoherent scatter radar; MHD; plasmavågor och instabiliteter; ickelinjära fenomen; solitoner och solitära vågor; jonosfär; solen: korona; inkoherent spridningsradar; MHD; NATURAL SCIENCES Physics Geocosmophysics and plasma physics; NATURVETENSKAP Fysik Geokosmofysik och plasmafysik; NATURAL SCIENCES Physics Geocosmophysics and plasma physics Space physics; NATURVETENSKAP Fysik Geokosmofysik och plasmafysik Rymdfysik; NATURAL SCIENCES Physics Geocosmophysics and plasma physics Plasma physics; NATURVETENSKAP Fysik Geokosmofysik och plasmafysik Plasmafysik; NATURAL SCIENCES Physics Other physics Non-linear dynamics; chaos; NATURVETENSKAP Fysik Övrig fysik Icke-linjär dynamik; kaos; fysik; Physics; rymd- och plasmafysik; Space and Plasma Physics;

    Abstract : This thesis addresses solitary waves and their significance for auroral particle acceleration, coronal heating and incoherent scatter radar spectra. Solitary waves are formed due to a balance of nonlinear and dispersive effects. READ MORE

  4. 4. The diagnostic potential of the He I D3 spectral line in the solar atmosphere

    University dissertation from Stockholm : Department of Astronomy, Stockholm University

    Author : Tine Libbrecht; Stockholms universitet.; [2019]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Sun; Line formation; Chromosphere; Spectro-Polarimetry; Flares; Reconnection; Astronomy; astronomi;

    Abstract : The research question of my PhD is in a way a simple one: what can observations of the He I D3 line teach us about the solar chromosphere? This optical spectral line at 5876 Å is generally formed in the upper chromosphere, and is sensitive to the local magnetic field. The He I D3 line is also indirectly sensitive to heating of the transition region and corona, since it is resulting from a transition that occurs between levels in the triplet system of neutral helium. READ MORE

  5. 5. The dynamic chromosphere Results and techniques with an observational approach

    University dissertation from Stockholm : Department of Astronomy, Stockholm University

    Author : Carolina Robustini; Stockholms universitet.; [2018]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Sun; chromosphere; jets; sunspots; imaging; spectropolarimetry; Astronomy; astronomi;

    Abstract : The chromosphere is a critical interface between the relatively cold photosphere and the hot corona. Its landscape is rich in very dynamic phenomena such as jets, spicules, and surges, which are thought to play an important role in the heating of the Sun’s upper atmosphere. READ MORE