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Updated: Sep 20, 2025
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X-ray Beam Induced Current Measurements for Multi-Modal X-ray Microscopy of Solar Cells
Published on: August 20, 2019
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Solar flare accelerates nearly all electrons in a large coronal volume
Gregory D Fleishman1, Gelu M Nita2, Bin Chen2
1Center for Solar-Terrestrial Research, New Jersey Institute of Technology, Newark, NJ, USA. gfleishm@njit.edu.
Nature
|June 8, 2022
Summary
Solar flares accelerate electrons, but hard X-ray observations miss some. Microwave data reveals the full electron acceleration volume, showing it
Area of Science:
- Solar physics
- Plasma astrophysics
- High-energy astrophysics
Background:
- Solar flares release magnetic energy, accelerating electrons.
- Hard X-ray observations are limited to dense regions, potentially missing accelerated electrons.
- Previous studies could not fully resolve the electron acceleration volume.
Purpose of the Study:
- To determine the true spatial extent of electron acceleration during solar flares.
- To investigate the distribution of thermal and non-thermal electrons in flare volumes.
- To understand the relationship between magnetic energy release and particle acceleration.
Main Methods:
- Utilized microwave observations for spatially resolved analysis.
- Derived distributions of thermal and non-thermal electrons.
- Compared observed electron distributions with flare plasma properties.
Main Results:
- Identified a distinct volume filled predominantly with non-thermal electrons.
- Observed this acceleration volume to be depleted of thermal plasma.
- Found this volume to be isolated from surrounding, more typical flare plasma.
Conclusions:
- Microwave observations reveal the complete electron acceleration region in solar flares.
- Efficient electron acceleration occurs in volumes of released magnetic energy, devoid of thermal plasma.
- This finding challenges previous assumptions based on limited observational volumes.
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