Book contents
- Frontmatter
- Dedication
- Contents
- Foreword
- Preface
- Abbreviations
- Part I Fundamentals of SOC
- Part II Astrophysical SOC Phenomena
- 4 Solar Flare Hard X-Rays
- 5 Solar Flare Soft X-Rays
- 6 Solar EUV Nanoflares
- 7 Solar Photospheric Events
- 8 Solar Radio Bursts
- 9 Coronal Mass Ejections
- 10 Solar Energetic Particle Events
- 11 Solar Wind
- 12 Magnetospheric Phenomena
- 13 Planetary Systems
- 14 Stellar Systems
- 15 Galactic and Black-Hole Systems
- Part III Conclusions
- References
- Index
11 - Solar Wind
from Part II - Astrophysical SOC Phenomena
Published online by Cambridge University Press: 05 December 2024
- Frontmatter
- Dedication
- Contents
- Foreword
- Preface
- Abbreviations
- Part I Fundamentals of SOC
- Part II Astrophysical SOC Phenomena
- 4 Solar Flare Hard X-Rays
- 5 Solar Flare Soft X-Rays
- 6 Solar EUV Nanoflares
- 7 Solar Photospheric Events
- 8 Solar Radio Bursts
- 9 Coronal Mass Ejections
- 10 Solar Energetic Particle Events
- 11 Solar Wind
- 12 Magnetospheric Phenomena
- 13 Planetary Systems
- 14 Stellar Systems
- 15 Galactic and Black-Hole Systems
- Part III Conclusions
- References
- Index
Summary
Can we claim that the dynamics of the solar wind is consistent with a SOC system? Observationally we find that magnetic field and kinetic energy fluctuations measured in the solar wind exhibit power law distributions, which is consistent with a SOC system. What about the driver, instability, and avalanches expected in a SOC system? The driver mechanism is the acceleration of the solar wind in the solar corona itself, a process that basically follows the hydrodynamic model of Parker (1958), and may be additionally complicated by the presence of nonlinear wave–particle interactions, such as ion-cyclotron resonance. Then, the instability threshold, triggering extreme bursts of magnetic field fluctuations, the avalanches of solar wind SOC events, can be caused by dissipation of Alfven waves, onset of turbulence, or by the ion-cyclotron instability. Thus, in principle the generalized SOC concept can be applied to the solar wind, if there is a system-wide threshold for an instability that causes extreme magnetic field fluctuations.
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- Chapter
- Information
- Power Laws in AstrophysicsSelf-Organized Criticality Systems, pp. 139 - 146Publisher: Cambridge University PressPrint publication year: 2024