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Updated: Nov 25, 2025
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Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
10.6K
Spectropolarimetric fluctuations in a sunspot chromosphere
M Stangalini1,2, D Baker3, G Valori3
1ASI, Italian Space Agency, Via del Politecnico snc, 00133 Rome, Italy.
Summary
New solar telescopes reveal Alfvénic perturbations in sunspots. Spectropolarimetric data link intensity and circular polarization fluctuations, suggesting these waves heat the solar atmosphere and accelerate the solar wind.
Area of Science:
- Solar physics
- Plasma astrophysics
- Stellar magnetic fields
Background:
- Advanced 4-meter class solar telescopes offer unprecedented spectropolarimetric accuracy.
- Magnetohydrodynamic (MHD) waves, especially Alfvénic fluctuations, are crucial for solar atmospheric heating and solar wind acceleration.
- The First Ionization Potential (FIP) effect in solar and stellar coronae is linked to MHD processes.
Purpose of the Study:
- To investigate the relationship between intensity and circular polarization (CP) fluctuations in sunspot chromospheres.
- To identify the presence and characteristics of MHD waves in the solar chromosphere.
Main Methods:
- Utilized state-of-the-art Interferometric BIdimensional Spectrometer (IBIS) observations.
- Analyzed spectropolarimetric data from a sunspot chromosphere.
- Correlated intensity and circular polarization fluctuations.
Main Results:
- A clear link was found between intensity and circular polarization fluctuations within a specific magnetic field inclination range.
- This correlation suggests the presence of Alfvénic perturbations in the observed sunspot region.
Conclusions:
- Alfvénic perturbations are likely present in sunspot chromospheres.
- Spectropolarimetric diagnostics are valuable tools for studying chromospheric magnetic fields and MHD wave dynamics.
- These findings contribute to understanding solar atmospheric heating and solar wind acceleration.
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