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Updated: May 5, 2026
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Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
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Irreversibility and Energy Transfer at Non-MHD Scales in a Magnetospheric Current Disruption Event
Giuseppe Consolini1, Paola De Michelis2
1INAF-Istituto di Astrofisica e Planetologia Spaziali, Via del Fosso del Cavaliere 100, 00133 Roma, Italy.
Entropy (Basel, Switzerland)
|March 28, 2025
Summary
Energy dissipation in space plasmas is complex. This study reveals irreversible processes at ion scales during a magnetospheric event, suggesting an energy cascade mechanism.
Area of Science:
- Space plasma physics
- Plasma turbulence
- Magnetospheric physics
Background:
- Understanding energy dissipation in non-collisional space plasmas is challenging.
- Irreversibility and scale-dependent processes are key areas of investigation.
- Recent advances utilize high-order correlations to study energy transfer in turbulent media.
Purpose of the Study:
- To explore irreversibility at non-MHD (Magnetohydrodynamics) scales.
- To analyze a specific magnetospheric current disruption event.
- To identify evidence of energy cascading mechanisms.
Main Methods:
- Analysis of asymmetric correlation functions.
- Assessment of fluctuation relation validity.
- Investigation of delayed coupling between different scales.
Main Results:
- Demonstrated the irreversible nature of fluctuations at ion and sub-ion scales.
- Provided potential evidence for an energy cascading mechanism.
- Observed cascading effects over short time delays.
Conclusions:
- Confirms irreversibility in space plasma processes at kinetic scales.
- Suggests a cascading mechanism contributes to energy dissipation.
- Highlights the importance of studying non-MHD effects in magnetospheric events.
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