| Original Articles |
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Selective Acceleration in Impulsive Solar Flares |
| WANG De-Yu |
| Purple Mountain Observatory, Chinese Academy of Sciences,
Nanjing 210008
National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012
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| Cite this article: |
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WANG De-Yu 2001 Chin. Phys. Lett. 18 1291-1293 |
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Abstract A plasma acceleration mechanism is proposed to explain the dramatic enhancement in the ratio of 3He/4He, (enhancement factor 102-103) observed in solar 3He-rich flares. Consideration that coronal plasma is mainly composed of hydrogen and helium ions, the hydrogen ion-helium ion hybrid waves and quasi-perpendicular waves can be excited by energetic electron beam during the impulsive solar flares. The frequencies of these waves are close to the 3He++ ion gyrofrequencies, but it is far from the 4He++ ion gyrofrequency. Most of these waves are selectively absorbed by 3He ions. These preheated 3He ions can be successively stochastic accelerated by Alfvén turbulence, when their velocities are larger than the local Alfvén velocity. It makes the ratio of 3He/4He dramatic enhanced and the acceleration energy spectrum of 3He ions forms a power-law distribution during the impulsive solar flares.
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| Keywords:
96.60.Rd
96.60.Fs
52.35.Hr
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Published: 01 September 2001
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| PACS: |
96.60.Rd
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96.60.Fs
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(Composition)
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52.35.Hr
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(Electromagnetic waves (e.g., electron-cyclotron, Whistler, Bernstein, upper hybrid, lower hybrid))
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