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Published on: June 9, 2016
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Plasmoid Formation and Strong Radiative Cooling in a Driven Magnetic Reconnection Experiment
R Datta1, K Chandler2, C E Myers2
1Plasma Science and Fusion Center, Massachusetts Institute of Technology, Massachusetts 02139, Cambridge, USA.
Physical Review Letters
|April 29, 2024
Summary
This study reveals plasmoid formation during rapid radiative cooling in magnetic reconnection, a key process in astrophysical plasmas. Fast-moving hotspots observed in X-ray images indicate plasmoid generation and high-energy radiation.
Area of Science:
- Plasma Physics
- Astrophysical Plasmas
- Magnetohydrodynamics
Background:
- Magnetic reconnection is crucial in astrophysical phenomena.
- Radiative cooling significantly impacts plasma dynamics.
- Understanding plasmoid formation is key to explaining high-energy emissions.
Purpose of the Study:
- Investigate plasmoid formation in rapidly radiatively cooled reconnection layers.
- Characterize the properties of these plasmoids and their emissions.
- Relate experimental findings to astrophysical plasma regimes.
Main Methods:
- Experimental study using Z machine and exploding aluminum wire arrays.
- Generation of a reconnection layer with high radiative cooling rate (S_{L}≈120).
- Time-gated X-ray imaging and spectroscopy to analyze emissions and plasma properties.
Main Results:
- Observed transient burst of >1 keV X-ray emission.
- Detected fast-moving hotspots (up to 50 km/s) consistent with plasmoids.
- Hotspots showed significantly higher temperatures (170 eV) and generated Al K-shell emission.
Conclusions:
- First experimental evidence of plasmoid formation in radiatively cooled reconnection.
- Findings provide insight into high-energy radiation generation in extreme astrophysical plasmas.
- Experimental results align with 3D resistive magnetohydrodynamic simulations.
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