Alfven Waves

A Study by Northumbria University (UK) confirmed direct observation of Alfven waves in the Sun’s corona, using data from Daniel K. Inouye Solar Telescope (DKIST), Hawaii — world’s largest ground-based solar telescope.

• It will help explain why the sun’s corona is ~200× hotter than the surface (2 million°F vs 10,000°F).

Alfven Waves and Coronal Heating Mechanism

• Definition: Alfven waves are low-frequency transverse magnetohydrodynamic (MHD) waves that travel along magnetic field lines in a plasma. 
  • They transport energy and momentum through charged particles without compressing the plasma.
• Physical Basis: It was predicted by Hannes Alfven (1942) as oscillations between magnetic tension and plasma inertia in magnetized fluids.
  • He received the 1970 Nobel Prize in Physics for his work on magnetohydrodynamics (MHD).
• Detection: Identified via red and blue Doppler shifts (Cryo-NIRSP instrument) showing twisting motion in coronal magnetic fields.
• Process/Mechanism: Energy from the solar surface  propagated as Alfven waves and  dissipated as heat in the corona.
  • These may account for ≈50% of total energy required to heat the corona.
• Interaction: Coexists with magnetic reconnection (another heating mechanism); together they influence solar wind acceleration and space weather.
• Significance: Advances understanding of solar plasma dynamics and energy transfer mechanisms.
  • Improves solar wind modeling, space weather forecasting, and understanding of stellar evolution.
• Challenges: Quantifying wave energy dissipation and integrating Alfven wave effects into predictive solar models.

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