Sökning: "coronal mass ejections"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden coronal mass ejections.

  1. 1. Combining Models of Coronal Mass Ejections and Solar Dynamos

    Författare :Jörn Warnecke; Axel Brandenburg; Juri Toomre; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Magnetohydrodynamics; convection; turbulence; solar dynamo; solar rotation; solar activity; coronal mass ejections; Astronomy; astronomi;

    Sammanfattning : Observations show that Coronal Mass Ejections (CMEs) are associated with twisted magnetic flux configurations. Conventionally, CMEs are modeled by shearing and twisting the footpoints of a certain distribution of magnetic flux at the solar surface and letting it evolve at the surface. LÄS MER

  3. 2. Flux emergence: flares and coronal mass ejections driven by dynamo action underneath the solar surface

    Författare :Jörn Warnecke; Axel Brandenburg; Dikpati Mausumi; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astronomy; astronomi; teoretisk astrofysik; Theoretical Astrophysics; Space and Plasma Physics; rymd- och plasmafysik;

    Sammanfattning : Helically shaped magnetic field structuresknown as coronal mass ejections (CMEs) are closely related to so-called eruptive flares. On the one hand, these events are broadly believed to be due tothe buoyant rise of magnetic flux tubes from the bottom of the convection zone to the photosphere where they form structures such as sunspots. LÄS MER

  4. 3. O+ outflow during geomagnetic storms observed by Cluster satellites

    Författare :Audrey Schillings; Hans Nilsson; Stephan Buchert; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Atmosfärsvetenskap; Atmospheric Science;

    Sammanfattning : The region of space dominated by the Sun's magnetic field is called the heliosphere. It envelops the entire solar system including Earth. Therefore, a strong coupling exists between the Sun and our planet. LÄS MER

  5. 4. How does O+ outflow vary with solar wind conditions?

    Författare :Audrey Schillings; Hans Nilsson; Rikard Slapak; Lars-Göran Westerberg; Christopher Cully; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Atmosfärsvetenskap; Atmospheric science;

    Sammanfattning : The entire solar system including Earth is enveloped in a region of space where the Sun’s magnetic field dominates, this region is called the heliosphere. Due to this position in the heliosphere, a strong coupling exists between the Sun and our planet. LÄS MER

  7. 5. Magnetic helicity in astrophysical dynamos

    Författare :Simon Candelaresi; Axel Brandenburg; Renzo Ricca; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astronomy; astronomi;

    Sammanfattning : The broad variety of ways in which magnetic helicity affects astrophysical systems, in particular dynamos, is discussed.The so-called alpha effect is responsible for the growth of large-scale magnetic fields. The conservation of magnetic helicity, however, quenches the alpha effect, in particular for high magnetic Reynolds numbers. LÄS MER