Heavy Ion Acceleration in Impulsive Solar Flares

• 来源期刊: 中国物理快报（英文版）
• 学科: 物理学
• 年，卷（期）: 2002,（7）
• 页码范围: 1027-1030
• 页数: 4页
• 分类号: O4
• 语种: 英文

摘要

The abundance enhancements of heavy ions Ne, Mg, Si and Fe in impulsive solar energetic particle (SEP) eventsare explained by a plasma acceleration mechanism. In consideration of the fact that the coronal plasma is mainlycomposed of hydrogen and helium ions, we think that theion-ion hybrid wave and quasi-perpendicular wave can.be excited by the energetic electron beam in impulsive solar flares. These waves may resonantly be absorbed byheavy ions when the frequencies of these waves are close to the second-harmonic gyrofrequencies of these heavyions. This requires the coronal plasma temperature to be located in the range ofT ～ (5 - 9) × 106 K in impulsivesolar flares and makes the average ionic charge state of these heavy ions in impulsive SEP events higher than theaverage ionic charge state of these heavy ions in gradual SEP events. These pre-heated and enhanced heavy ionsin impulsive SEP events.