Sökning: "Galactic Magnetic Fields"

Visar resultat 1 - 5 av 10 avhandlingar innehållade orden Galactic Magnetic Fields.

  1. 1. Generation of magnetic fields on galactic scale

    Författare :Fabio Del Sordo; Axel Brandenburg; Oliver Gressel; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Magnetic fields; galaxies; Astronomy; astronomi;

    Sammanfattning : In these pages we will go through the topic of astrophysical magnetic fields, focusing on galactic fields, their observation and the theories that have been developed for a proper understanding of the these physical phenomena.We review the main work in the study of galactic magnetic fields, often seeing how it is important to deal with problems of general validity in order to be able to point out the right elements needed for a correct interpretation of specific situations. LÄS MER

  3. 2. Transport, Turbulence and Instabilities in Cosmic Magnetic Fields

    Författare :Giuseppe Di Bernardo; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Cosmic Rays; Interstella Medium; Galactic Magnetic Fields; Magnetohydrodynamics Turbulence; Accretion Discs;

    Sammanfattning : This decade has seen a large number of space missions, which, alongside ground-based radio, optical and gamma-ray telescopes, have enabled a deep insight into the non-thermal astrophysical environments. Interstellar Medium (ISM), Supernovae Remnants (SNRs) and Black-Hole (BH) accretion discs (ADs) are only a few examples of natural habitat of interaction of relativistic particles and magnetic fields, largely mediated by the action of the turbulence. LÄS MER

  4. 3. Generation of magnetic fields in plasmas

    Författare :Nitin Shukla; Gert Brodin; Dusan Jovanovic; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Relativistic and non-relativistic plasma outflows are quite ubiquitous in astrophysical scenarios, as well as in laboratory plasmas. The propagation of relativistic and non- relativistic charged particle beams in background plasmas provides return currents in the opposite direction and interactions between the currents then drive several plasma instabilities involving the longitudinal (electrostatic instabilities) and trans- verse (electromagnetic instability) modes. LÄS MER

  5. 4. 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

  7. 5. From irrotational flows to turbulent dynamos

    Författare :Fabio Del Sordo; Axel Brandenburg; Mordecai-Mark Mac Low; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; astrophysics; magnetic fields; insterstellar medium; MHD; dynamo; turbulence; instability; Astronomy; astronomi;

    Sammanfattning : Many of the celestial bodies we know are found to be magnetized:the Earth, many of the planets so far discovered, the Sun and other stars,the interstellar space, the Milky Way and other galaxies.The reason for that is still to be fully understood, and this work is meant to be a step in that direction. LÄS MER